diff --git a/frameworks/native/backup_ext/BUILD.gn b/frameworks/native/backup_ext/BUILD.gn
index ec99742a2db2cd5ce9fa3e6b36b69f3b673a3b68..ce6381303c63f30c1522a38c77ffe09d21dfb46c 100644
--- a/frameworks/native/backup_ext/BUILD.gn
+++ b/frameworks/native/backup_ext/BUILD.gn
@@ -21,6 +21,8 @@ ohos_shared_library("backup_extension_ability_native") {
     "src/ext_backup_loader.cpp",
     "src/ext_extension.cpp",
     "src/ext_extension_stub.cpp",
+    "src/tar_file.cpp",
+    "src/untar_file.cpp",
   ]
 
   defines = [
diff --git a/frameworks/native/backup_ext/src/ext_extension.cpp b/frameworks/native/backup_ext/src/ext_extension.cpp
index 485f0b64346c3eac8320ad221c9341a9df502bc8..a2ce1fd81dab0c574d9171feeb7e70b430e38b85 100644
--- a/frameworks/native/backup_ext/src/ext_extension.cpp
+++ b/frameworks/native/backup_ext/src/ext_extension.cpp
@@ -42,6 +42,8 @@
 #include "b_tarball/b_tarball_factory.h"
 #include "filemgmt_libhilog.h"
 #include "service_proxy.h"
+#include "tar_file.h"
+#include "untar_file.h"
 
 namespace OHOS::FileManagement::Backup {
 const string DEFAULT_TAR_PKG = "1.tar";
@@ -111,7 +113,7 @@ ErrCode BackupExtExtension::HandleClear()
     return ERR_OK;
 }
 
-static ErrCode IndexFileReady(const map<string, tuple<string, struct stat, bool>> &pkgInfo, sptr<IService> proxy)
+static ErrCode IndexFileReady(const TarMap &pkgInfo, sptr<IService> proxy)
 {
     BJsonCachedEntity<BJsonEntityExtManage> cachedEntity(
         UniqueFd(open(INDEX_FILE_BACKUP.data(), O_RDWR | O_CREAT, S_IRUSR | S_IWUSR)));
@@ -235,15 +237,14 @@ static bool IsUserTar(const string &tarFile, const string &indexFile)
     return false;
 }
 
-static map<string, tuple<string, struct stat, bool>> GetBigFileInfo(const vector<string> &includes,
-                                                                    const vector<string> &excludes)
+static pair<TarMap, vector<string>> GetFileInfos(const vector<string> &includes, const vector<string> &excludes)
 {
-    auto [errCode, files] = BDir::GetBigFiles(includes, excludes);
+    auto [errCode, files, smallFiles] = BDir::GetBigFiles(includes, excludes);
     if (errCode != 0) {
         return {};
     }
 
-    auto GetStringHash = [](const map<string, tuple<string, struct stat, bool>> &m, const string &str) -> string {
+    auto GetStringHash = [](const TarMap &m, const string &str) -> string {
         ostringstream strHex;
         strHex << hex;
 
@@ -260,7 +261,7 @@ static map<string, tuple<string, struct stat, bool>> GetBigFileInfo(const vector
         return name;
     };
 
-    map<string, tuple<string, struct stat, bool>> bigFiles;
+    TarMap bigFiles;
     for (const auto &item : files) {
         string md5Name = GetStringHash(bigFiles, item.first);
         if (!md5Name.empty()) {
@@ -268,7 +269,7 @@ static map<string, tuple<string, struct stat, bool>> GetBigFileInfo(const vector
         }
     }
 
-    return bigFiles;
+    return {bigFiles, smallFiles};
 }
 
 int BackupExtExtension::DoBackup(const BJsonEntityExtensionConfig &usrConfig)
@@ -287,7 +288,7 @@ int BackupExtExtension::DoBackup(const BJsonEntityExtensionConfig &usrConfig)
     vector<string> excludes = usrConfig.GetExcludes();
 
     // 大文件处理
-    auto bigFileInfo = GetBigFileInfo(includes, excludes);
+    auto [bigFileInfo, smallFiles] = GetFileInfos(includes, excludes);
     for (const auto &item : bigFileInfo) {
         auto filePath = std::get<0>(item.second);
         if (!filePath.empty()) {
@@ -295,18 +296,10 @@ int BackupExtExtension::DoBackup(const BJsonEntityExtensionConfig &usrConfig)
         }
     }
 
-    string tarName = path + DEFAULT_TAR_PKG;
-    string root = "/";
-
-    // 打包
-    auto tarballTar = BTarballFactory::Create("cmdline", tarName);
-    (tarballTar->tar)(root, {includes.begin(), includes.end()}, {excludes.begin(), excludes.end()});
-
-    struct stat sta = {};
-    if (stat(tarName.data(), &sta) == -1) {
-        HILOGE("failed to invoke the system function stat, %{public}s", tarName.c_str());
-    }
-    bigFileInfo.emplace(DEFAULT_TAR_PKG, make_tuple(tarName, sta, false));
+    // 分片打包
+    TarMap tarMap {};
+    TarFile::GetInstance().Packet(smallFiles, "part", path, tarMap);
+    bigFileInfo.insert(tarMap.begin(), tarMap.end());
 
     auto proxy = ServiceProxy::GetInstance();
     if (proxy == nullptr) {
@@ -331,14 +324,7 @@ int BackupExtExtension::DoRestore(const string &fileName)
     // REM: 解压启动Extension时即挂载好的备份目录中的数据
     string path = string(BConstants::PATH_BUNDLE_BACKUP_HOME).append(BConstants::SA_BUNDLE_BACKUP_RESTORE);
     string tarName = path + fileName;
-    HILOGI("tarName:%{public}s, fileName:%{public}s", tarName.c_str(), fileName.c_str());
-
-    auto tarballFunc = BTarballFactory::Create("cmdline", tarName);
-    if (extension_->WasFromSpeicalVersion() || extension_->UseFullBackupOnly()) {
-        (tarballFunc->untar)(path);
-    } else {
-        (tarballFunc->untar)("/");
-    }
+    UntarFile::GetInstance().UnPacket(tarName, "/");
     HILOGI("Application recovered successfully, package path is %{public}s", tarName.c_str());
 
     return ERR_OK;
@@ -433,13 +419,17 @@ static void RestoreBigFiles()
             HILOGE("file path is empty. %{public}s", filePath.c_str());
             continue;
         }
-        if (rename(fileName.data(), filePath.data()) != 0) {
-            HILOGE("failed to rename the file, try to copy it. err = %{public}d", errno);
-            if (!BFile::CopyFile(fileName, filePath)) {
-                HILOGE("failed to copy the file. err = %{public}d", errno);
-                continue;
+        if (!BFile::CopyFile(fileName, filePath)) {
+            HILOGE("failed to copy the file. err = %{public}d", errno);
+            continue;
+        }
+        if (chmod(filePath.c_str(), item.sta.st_mode) != 0) {
+            HILOGE("Failed to chmod %{public}s, err = %{public}d", filePath.c_str(), errno);
+        }
+        if (fileName != filePath) {
+            if (!RemoveFile(fileName)) {
+                HILOGE("Failed to delete the big file %{public}s", fileName.c_str());
             }
-            HILOGI("succeed to rename or copy the file");
         }
         set<string> lks = cache.GetHardLinkInfo(item.hashName);
         for (const auto &lksPath : lks) {
@@ -459,15 +449,21 @@ static void RestoreBigFiles()
 static void DeleteBackupTars()
 {
     // The directory include tars and manage.json which would be deleted
-    string path = string(BConstants::PATH_BUNDLE_BACKUP_HOME).append(BConstants::SA_BUNDLE_BACKUP_RESTORE);
-    string tarPath = path + DEFAULT_TAR_PKG;
-    string indexPath = path + string(BConstants::EXT_BACKUP_MANAGE);
-    if (!RemoveFile(tarPath)) {
-        HILOGE("Failed to delete the backup tar %{public}s", tarPath.c_str());
+    BJsonCachedEntity<BJsonEntityExtManage> cachedEntity(UniqueFd(open(INDEX_FILE_RESTORE.data(), O_RDONLY)));
+    auto cache = cachedEntity.Structuralize();
+    auto info = cache.GetExtManage();
+    auto path = string(BConstants::PATH_BUNDLE_BACKUP_HOME).append(BConstants::SA_BUNDLE_BACKUP_RESTORE);
+    for (auto &item : info) {
+        if (ExtractFileExt(item) != "tar" || IsUserTar(item, INDEX_FILE_RESTORE)) {
+            continue;
+        }
+        string tarPath = path + item;
+        if (!RemoveFile(tarPath)) {
+            HILOGE("Failed to delete the backup tar %{public}s", tarPath.c_str());
+        }
     }
-
-    if (!RemoveFile(indexPath)) {
-        HILOGE("Failed to delete the backup index %{public}s", indexPath.c_str());
+    if (!RemoveFile(INDEX_FILE_RESTORE)) {
+        HILOGE("Failed to delete the backup index %{public}s", INDEX_FILE_RESTORE.c_str());
     }
 }
 
@@ -484,7 +480,7 @@ void BackupExtExtension::AsyncTaskRestore()
 
             // 解压
             int ret = ERR_OK;
-            for (auto item : tars) { // 处理要解压的tar文件
+            for (auto item : tars) {
                 if (ExtractFileExt(item) == "tar" && !IsUserTar(item, INDEX_FILE_RESTORE)) {
                     ret = ptr->DoRestore(item);
                 }
diff --git a/tests/unittests/backup_utils/b_filesystem/b_dir_test.cpp b/tests/unittests/backup_utils/b_filesystem/b_dir_test.cpp
index e0c78540b4990b489415cfd43a22ccb9051914a9..f89595510d083390afd03c5fb04b736597362cc3 100644
--- a/tests/unittests/backup_utils/b_filesystem/b_dir_test.cpp
+++ b/tests/unittests/backup_utils/b_filesystem/b_dir_test.cpp
@@ -104,7 +104,7 @@ HWTEST_F(BDirTest, b_dir_GetBigFiles_0100, testing::ext::TestSize.Level1)
         EXPECT_EQ(ret, 0);
         vector<string> includes = {rootDir};
         vector<string> excludes = {filePath2};
-        auto [errCode, mpNameToStat] = BDir::GetBigFiles(includes, excludes);
+        auto [errCode, mpNameToStat, smallFiles] = BDir::GetBigFiles(includes, excludes);
         EXPECT_EQ(errCode, ERR_OK);
         EXPECT_EQ(mpNameToStat.at(filePath1).st_size, 1024 * 1024 * 1025);
         EXPECT_EQ(mpNameToStat.find(filePath2), mpNameToStat.end());
@@ -130,7 +130,7 @@ HWTEST_F(BDirTest, b_dir_GetBigFiles_0200, testing::ext::TestSize.Level1)
     try {
         vector<string> includes = {{}, {}};
         vector<string> excludes = {{}};
-        auto [errCode, mpNameToStat] = BDir::GetBigFiles(includes, excludes);
+        auto [errCode, mpNameToStat, smallFiles] = BDir::GetBigFiles(includes, excludes);
         EXPECT_EQ(errCode, ERR_OK);
     } catch (...) {
         EXPECT_TRUE(false);
@@ -171,7 +171,7 @@ HWTEST_F(BDirTest, b_dir_GetBigFiles_0300, testing::ext::TestSize.Level1)
         system(touchFilePrefix.append("c.txt").c_str());
         vector<string> includes = {preparedDir + string("/*"), preparedDir + string("test")};
         vector<string> excludes = {preparedDir + string("/test/test1/test2"), {}};
-        auto [errCode, mpNameToStat] = BDir::GetBigFiles(includes, excludes);
+        auto [errCode, mpNameToStat, smallFiles] = BDir::GetBigFiles(includes, excludes);
         EXPECT_EQ(errCode, ERR_OK);
     } catch (...) {
         EXPECT_TRUE(false);
diff --git a/utils/include/b_filesystem/b_dir.h b/utils/include/b_filesystem/b_dir.h
index 27762942eef16c76ac587551b51292ab580658a6..753529cb63e2eb48567c061412314a7ceb966072 100644
--- a/utils/include/b_filesystem/b_dir.h
+++ b/utils/include/b_filesystem/b_dir.h
@@ -46,8 +46,8 @@ public:
      * @param excludes 需要排除的文件及目录集合
      * @return 错误码、大文件名集合
      */
-    static std::pair<ErrCode, std::map<std::string, struct stat>> GetBigFiles(const std::vector<std::string> &includes,
-                                                                              const std::vector<std::string> &excludes);
+    static std::tuple<ErrCode, std::map<std::string, struct stat>, std::vector<std::string>> GetBigFiles(
+        const std::vector<std::string> &includes, const std::vector<std::string> &excludes);
 
     /**
      * @brief Get the Dirs object
diff --git a/utils/include/b_json/b_json_entity_caps.h b/utils/include/b_json/b_json_entity_caps.h
index db51d4270fed89cbd12bf797ba0f7770f43b08de..e52dd173b16f5fbcadde0e1c41cede18d445582b 100644
--- a/utils/include/b_json/b_json_entity_caps.h
+++ b/utils/include/b_json/b_json_entity_caps.h
@@ -110,7 +110,6 @@ public:
             string restoreDeps("");
             if (item.isMember("restoreDeps") && item["restoreDeps"].isString()) {
                 restoreDeps = item["restoreDeps"].asString();
-                HILOGI("restoreDeps is %{public}s", restoreDeps.data());
             }
             bundleInfos.emplace_back(BundleInfo {item["name"].asString(), item["versionCode"].asUInt(),
                                                  item["versionName"].asString(), item["spaceOccupied"].asInt64(),
diff --git a/utils/include/b_resources/b_constants.h b/utils/include/b_resources/b_constants.h
index e9adc535625af4fa1b460fd7797b10b57a1a3066..70c2ed6da950429c94f86a8cd223fdecd33b3b72 100644
--- a/utils/include/b_resources/b_constants.h
+++ b/utils/include/b_resources/b_constants.h
@@ -62,8 +62,8 @@ constexpr int DECIMAL_BASE = 10; // 十进制基数
 constexpr int HEADER_SIZE = 512;         // 打包文件头部Header结构体大小
 constexpr int BLOCK_SIZE = 512;          // 打包文件数据段尾部补充的全零字节块上限大小
 constexpr int BLOCK_PADDING_SIZE = 1024; // 打包文件尾部追加的全零字节块大小
-constexpr off_t BIG_FILE_BOUNDARY = 1024 * 1024 * 1024; // 大文件边界
-constexpr unsigned long BIG_FILE_NAME_SIZE = 16;        // 大文件名长度(hash处理)
+constexpr off_t BIG_FILE_BOUNDARY = 2 * 1024 * 1024; // 大文件边界
+constexpr unsigned long BIG_FILE_NAME_SIZE = 16;     // 大文件名长度(hash处理)
 
 constexpr int PATHNAME_MAX_SIZE = 100; // 打包文件头部Header结构体各字段数组/字符串大小。
 constexpr int MODE_MAX_SIZE = 8;
diff --git a/utils/src/b_filesystem/b_dir.cpp b/utils/src/b_filesystem/b_dir.cpp
index 045a96ce51515abcc7fee1c133e695205c2e2a06..cbfc884c80c06786ece88cc3a4fce3e9e22eeb2e 100644
--- a/utils/src/b_filesystem/b_dir.cpp
+++ b/utils/src/b_filesystem/b_dir.cpp
@@ -35,13 +35,40 @@
 namespace OHOS::FileManagement::Backup {
 using namespace std;
 
-static pair<ErrCode, map<string, struct stat>> GetDirFilesDetail(const string &path, bool recursion, off_t size = -1)
+static bool IsEmptyDirectory(const string &path)
+{
+    DIR *dir = opendir(path.c_str());
+    if (dir == nullptr) {
+        return false;
+    }
+    bool isEmpty = true;
+    struct dirent *entry;
+    while ((entry = readdir(dir)) != nullptr) {
+        if (entry->d_type != DT_DIR || (strcmp(entry->d_name, ".") != 0 && strcmp(entry->d_name, "..") != 0)) {
+            isEmpty = false;
+            break;
+        }
+    }
+    closedir(dir);
+    return isEmpty;
+}
+
+static tuple<ErrCode, map<string, struct stat>, vector<string>> GetDirFilesDetail(const string &path,
+                                                                                  bool recursion,
+                                                                                  off_t size = -1)
 {
     map<string, struct stat> files;
+    vector<string> smallFiles;
+
+    if (IsEmptyDirectory(path)) {
+        smallFiles.emplace_back(path);
+        return {BError(BError::Codes::OK).GetCode(), files, smallFiles}; 
+    }
+
     unique_ptr<DIR, function<void(DIR *)>> dir = {opendir(path.c_str()), closedir};
     if (!dir) {
         HILOGE("Invalid directory path: %{private}s", path.c_str());
-        return {BError(errno).GetCode(), files};
+        return {BError(errno).GetCode(), files, smallFiles};
     }
 
     struct dirent *ptr = nullptr;
@@ -54,12 +81,13 @@ static pair<ErrCode, map<string, struct stat>> GetDirFilesDetail(const string &p
                 continue;
             }
 
-            auto [errCode, subfiles] =
+            auto [errCode, subFiles, subSmallFiles] =
                 GetDirFilesDetail(IncludeTrailingPathDelimiter(path) + string(ptr->d_name), recursion, size);
             if (errCode != 0) {
-                return {errCode, files};
+                return {errCode, files, smallFiles};
             }
-            files.merge(subfiles);
+            files.merge(subFiles);
+            smallFiles.insert(smallFiles.end(), subSmallFiles.begin(), subSmallFiles.end());
         } else if (ptr->d_type == DT_LNK) {
             continue;
         } else {
@@ -69,6 +97,8 @@ static pair<ErrCode, map<string, struct stat>> GetDirFilesDetail(const string &p
                 continue;
             }
             if (sta.st_size < size) {
+                HILOGI("Find small file %{public}s", fileName.data());
+                smallFiles.emplace_back(fileName);
                 continue;
             }
             HILOGI("Find big file");
@@ -76,7 +106,7 @@ static pair<ErrCode, map<string, struct stat>> GetDirFilesDetail(const string &p
         }
     }
 
-    return {BError(BError::Codes::OK).GetCode(), files};
+    return {BError(BError::Codes::OK).GetCode(), files, smallFiles};
 }
 
 tuple<ErrCode, vector<string>> BDir::GetDirFiles(const string &path)
@@ -136,19 +166,23 @@ static set<string> ExpandPathWildcard(const vector<string> &vec)
     return filteredPath;
 }
 
-pair<ErrCode, map<string, struct stat>> BDir::GetBigFiles(const vector<string> &includes,
-                                                          const vector<string> &excludes)
+tuple<ErrCode, map<string, struct stat>, vector<string>> BDir::GetBigFiles(const vector<string> &includes,
+                                                                           const vector<string> &excludes)
 {
     set<string> inc = ExpandPathWildcard(includes);
 
     map<string, struct stat> incFiles;
+    vector<string> incSmallFiles;
     for (const auto &item : inc) {
-        auto [errCode, files] =
+        auto [errCode, files, smallFiles] =
             OHOS::FileManagement::Backup::GetDirFilesDetail(item, true, BConstants::BIG_FILE_BOUNDARY);
         if (errCode == 0) {
             int32_t num = static_cast<int32_t>(files.size());
             HILOGI("found big files. total number is : %{public}d", num);
             incFiles.merge(move(files));
+
+            HILOGI("found small files. total number is : %{public}d", static_cast<int32_t>(smallFiles.size()));
+            incSmallFiles.insert(incSmallFiles.end(), smallFiles.begin(), smallFiles.end());
         }
     }
 
@@ -172,9 +206,9 @@ pair<ErrCode, map<string, struct stat>> BDir::GetBigFiles(const vector<string> &
             bigFiles[item.first] = item.second;
         }
     }
-    int32_t num = static_cast<int32_t>(bigFiles.size());
-    HILOGI("total number of big files is %{public}d", num);
-    return {ERR_OK, move(bigFiles)};
+    HILOGI("total number of big files is %{public}d", static_cast<int32_t>(bigFiles.size()));
+    HILOGI("total number of small files is %{public}d", static_cast<int32_t>(incSmallFiles.size()));
+    return {ERR_OK, move(bigFiles), move(incSmallFiles)};
 }
 
 vector<string> BDir::GetDirs(const vector<string_view> &paths)
diff --git a/utils/src/b_json/b_json_entity_ext_manage.cpp b/utils/src/b_json/b_json_entity_ext_manage.cpp
index bff04e1d71d86cc0fe532ac6e516646d2c5b4b24..5b9f3e2f3b57f148cd02d44318006cebb941d253 100644
--- a/utils/src/b_json/b_json_entity_ext_manage.cpp
+++ b/utils/src/b_json/b_json_entity_ext_manage.cpp
@@ -58,6 +58,7 @@ Json::Value Stat2JsonValue(struct stat sta)
     Json::Value value;
 
     value["st_size"] = static_cast<int64_t>(sta.st_size);
+    value["st_mode"] = static_cast<int32_t>(sta.st_mode);
     value["st_atim"]["tv_sec"] = static_cast<int64_t>(sta.st_atim.tv_sec);
     value["st_atim"]["tv_nsec"] = static_cast<int64_t>(sta.st_atim.tv_nsec);
     value["st_mtim"]["tv_sec"] = static_cast<int64_t>(sta.st_mtim.tv_sec);
@@ -75,6 +76,7 @@ struct stat JsonValue2Stat(const Json::Value &value)
     }
 
     sta.st_size = value.isMember("st_size") && value["st_size"].isInt64() ? value["st_size"].asInt64() : 0;
+    sta.st_mode = value.isMember("st_mode") && value["st_mode"].isInt() ? value["st_mode"].asInt() : 0;
     if (value.isMember("st_atim")) {
         sta.st_atim.tv_sec = value["st_atim"].isMember("tv_sec") && value["st_atim"]["tv_sec"].isInt64()
                                  ? value["st_atim"]["tv_sec"].asInt64()