diff --git a/tests/unittests/backup_ext/tar_file_test.cpp b/tests/unittests/backup_ext/tar_file_test.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..8aaa0f2f16218142d66193691090d1f521ddad72
--- /dev/null
+++ b/tests/unittests/backup_ext/tar_file_test.cpp
@@ -0,0 +1,399 @@
+/*
+ * Copyright (c) 2022-2023 Huawei Device Co., Ltd.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * @tc.number: SUB_Tar_File_TraversalFile_0300
+ * @tc.name: SUB_Tar_File_TraversalFile_0300
+ * @tc.desc: 测试 TraversalFile 接口
+ * @tc.size: MEDIUM
+ * @tc.type: FUNC
+ * @tc.level Level 1
+ * @tc.require: I6F3GV
+ */
+HWTEST_F(TarFileTest, SUB_Tar_File_TraversalFile_0300, testing::ext::TestSize.Level1)
+{
+    GTEST_LOG_(INFO) << "TarFileTest-begin SUB_Tar_File_TraversalFile_0300";
+    try {
+        // 预置文件和目录
+        TestManager tm("SUB_Tar_File_TraversalFile_0300");
+        string root = tm.GetRootDirCurTest();
+        string testDir = root + "/testdir";
+        if (mkdir(testDir.data(), S_IRWXU) && errno != EEXIST) {
+            GTEST_LOG_(INFO) << " invoked mkdir failure, errno :" << errno;
+            throw BError(errno);
+        }
+        string tarFile = root + "test.tar";
+        TarFile::GetInstance().currentTarFile_ = fopen(tarFile.c_str(), "wb+");
+        ASSERT_TRUE(TarFile::GetInstance().currentTarFile_ != nullptr);
+
+        string filePath(testDir);
+        bool ret = TarFile::GetInstance().TraversalFile(filePath);
+        EXPECT_TRUE(ret);
+        EXPECT_EQ(TarFile::GetInstance().currentFileName_, "");
+        EXPECT_EQ(TarFile::GetInstance().fileCount_, 1);
+        ClearCache();
+    } catch (...) {
+        EXPECT_TRUE(false);
+        GTEST_LOG_(INFO) << "TarFileTest-an exception occurred by TarFile.";
+    }
+    GTEST_LOG_(INFO) << "TarFileTest-end SUB_Tar_File_TraversalFile_0300";
+}
+
+/**
+ * @tc.number: SUB_Tar_File_AddFile_0100
+ * @tc.name: SUB_Tar_File_AddFile_0100
+ * @tc.desc: 测试 AddFile 接口
+ * @tc.size: MEDIUM
+ * @tc.type: FUNC
+ * @tc.level Level 1
+ * @tc.require: I6F3GV
+ */
+HWTEST_F(TarFileTest, SUB_Tar_File_AddFile_0100, testing::ext::TestSize.Level1)
+{
+    GTEST_LOG_(INFO) << "TarFileTest-begin SUB_Tar_File_AddFile_0100";
+    try {
+        CreateTarFile("SUB_Tar_File_AddFile_0100");
+        string fileName("");
+        struct stat st {};
+        bool isSplit = false;
+        bool ret = TarFile::GetInstance().AddFile(fileName, st, isSplit);
+        EXPECT_TRUE(ret);
+        EXPECT_TRUE(TarFile::GetInstance().currentFileName_.empty());
+        ClearCache();
+    } catch (...) {
+        EXPECT_TRUE(false);
+        GTEST_LOG_(INFO) << "TarFileTest-an exception occurred by TarFile.";
+    }
+    GTEST_LOG_(INFO) << "TarFileTest-end SUB_Tar_File_AddFile_0100";
+}
+
+/**
+ * @tc.number: SUB_Tar_File_AddFile_0300
+ * @tc.name: SUB_Tar_File_AddFile_0300
+ * @tc.desc: 测试 AddFile 接口
+ * @tc.size: MEDIUM
+ * @tc.type: FUNC
+ * @tc.level Level 1
+ * @tc.require: I6F3GV
+ */
+HWTEST_F(TarFileTest, SUB_Tar_File_AddFile_0300, testing::ext::TestSize.Level1)
+{
+    GTEST_LOG_(INFO) << "TarFileTest-begin SUB_Tar_File_AddFile_0300";
+    try {
+        // 预置文件和目录
+        TestManager tm("SUB_Tar_File_AddFile_0300");
+        string root = tm.GetRootDirCurTest();
+        string testDir = root + "/testdir";
+        if (mkdir(testDir.data(), S_IRWXU) && errno != EEXIST) {
+            GTEST_LOG_(INFO) << " invoked mkdir failure, errno :" << errno;
+            throw BError(errno);
+        }
+
+        string fileName(testDir);
+        struct stat st {};
+        if (lstat(fileName.c_str(), &st) != 0) {
+            GTEST_LOG_(INFO) << " invoked lstat failure, errno :" << errno;
+            throw BError(errno);
+        }
+
+        string tarFile = root + "test.tar";
+        TarFile::GetInstance().currentTarFile_ = fopen(tarFile.c_str(), "wb+");
+        ASSERT_TRUE(TarFile::GetInstance().currentTarFile_ != nullptr);
+
+        bool isSplit = false;
+        bool ret = TarFile::GetInstance().AddFile(fileName, st, isSplit);
+        EXPECT_TRUE(ret);
+        EXPECT_TRUE(TarFile::GetInstance().currentFileName_.empty());
+        ClearCache();
+    } catch (...) {
+        EXPECT_TRUE(false);
+        GTEST_LOG_(INFO) << "TarFileTest-an exception occurred by TarFile.";
+    }
+    GTEST_LOG_(INFO) << "TarFileTest-end SUB_Tar_File_AddFile_0300";
+}
+
+/**
+ * @tc.number: SUB_Tar_File_WriteFileContent_0100
+ * @tc.name: SUB_Tar_File_WriteFileContent_0100
+ * @tc.desc: 测试 WriteFileContent 接口
+ * @tc.size: MEDIUM
+ * @tc.type: FUNC
+ * @tc.level Level 1
+ * @tc.require: I6F3GV
+ */
+HWTEST_F(TarFileTest, SUB_Tar_File_WriteFileContent_0100, testing::ext::TestSize.Level1)
+{
+    GTEST_LOG_(INFO) << "TarFileTest-begin SUB_Tar_File_WriteFileContent_0100";
+    try {
+        string fileName("");
+        off_t size = 0;
+        bool ret = TarFile::GetInstance().WriteFileContent(fileName, size);
+        EXPECT_FALSE(ret);
+        ClearCache();
+    } catch (...) {
+        EXPECT_TRUE(false);
+        GTEST_LOG_(INFO) << "TarFileTest-an exception occurred by TarFile.";
+    }
+    GTEST_LOG_(INFO) << "TarFileTest-end SUB_Tar_File_WriteFileContent_0100";
+}
+
+/**
+ * @tc.number: SUB_Tar_File_WriteFileContent_0200
+ * @tc.name: SUB_Tar_File_WriteFileContent_0200
+ * @tc.desc: 测试 WriteFileContent 接口
+ * @tc.size: MEDIUM
+ * @tc.type: FUNC
+ * @tc.level Level 1
+ * @tc.require: I6F3GV
+ */
+HWTEST_F(TarFileTest, SUB_Tar_File_WriteFileContent_0200, testing::ext::TestSize.Level1)
+{
+    GTEST_LOG_(INFO) << "TarFileTest-begin SUB_Tar_File_WriteFileContent_0200";
+    try {
+        // 预置文件和目录
+        TestManager tm("SUB_Tar_File_WriteFileContent_0200");
+        string root = tm.GetRootDirCurTest();
+        string testDir = root + "/testdir";
+        if (mkdir(testDir.data(), S_IRWXU) && errno != EEXIST) {
+            GTEST_LOG_(INFO) << " invoked mkdir failure, errno :" << errno;
+            throw BError(errno);
+        }
+        string aFile = testDir + "/a.txt";
+        SaveStringToFile(aFile, "hello");
+
+        string tarFile = root + "test.tar";
+        TarFile::GetInstance().currentTarFile_ = fopen(tarFile.c_str(), "wb+");
+        ASSERT_TRUE(TarFile::GetInstance().currentTarFile_ != nullptr);
+
+        string fileName(aFile);
+        struct stat st {};
+        if (lstat(fileName.c_str(), &st) != 0) {
+            GTEST_LOG_(INFO) << " invoked lstat failure, errno :" << errno;
+            throw BError(errno);
+        }
+        off_t size = st.st_size;
+        TarFile::GetInstance().ioBuffer_.resize(READ_BUFF_SIZE);
+        bool ret = TarFile::GetInstance().WriteFileContent(fileName, size);
+        EXPECT_TRUE(ret);
+        ClearCache();
+    } catch (...) {
+        EXPECT_TRUE(false);
+        GTEST_LOG_(INFO) << "TarFileTest-an exception occurred by TarFile.";
+    }
+    GTEST_LOG_(INFO) << "TarFileTest-end SUB_Tar_File_WriteFileContent_0200";
+}
+
+/**
+ * @tc.number: SUB_Tar_File_SplitWriteAll_0100
+ * @tc.name: SUB_Tar_File_SplitWriteAll_0100
+ * @tc.desc: 测试 SplitWriteAll 接口
+ * @tc.size: MEDIUM
+ * @tc.type: FUNC
+ * @tc.level Level 1
+ * @tc.require: I6F3GV
+ */
+HWTEST_F(TarFileTest, SUB_Tar_File_SplitWriteAll_0100, testing::ext::TestSize.Level1)
+{
+    GTEST_LOG_(INFO) << "TarFileTest-begin SUB_Tar_File_SplitWriteAll_0100";
+    try {
+        vector<uint8_t> ioBuffer;
+        int read = 0;
+        bool isFilled = false;
+        int ret = TarFile::GetInstance().SplitWriteAll(ioBuffer, read, isFilled);
+        EXPECT_EQ(ret, 0);
+        ClearCache();
+    } catch (...) {
+        EXPECT_TRUE(false);
+        GTEST_LOG_(INFO) << "TarFileTest-an exception occurred by TarFile.";
+    }
+    GTEST_LOG_(INFO) << "TarFileTest-end SUB_Tar_File_SplitWriteAll_0100";
+}
+
+/**
+ * @tc.number: SUB_Tar_File_SplitWriteAll_0200
+ * @tc.name: SUB_Tar_File_SplitWriteAll_0200
+ * @tc.desc: 测试 SplitWriteAll 接口
+ * @tc.size: MEDIUM
+ * @tc.type: FUNC
+ * @tc.level Level 1
+ * @tc.require: I6F3GV
+ */
+HWTEST_F(TarFileTest, SUB_Tar_File_SplitWriteAll_0200, testing::ext::TestSize.Level1)
+{
+    GTEST_LOG_(INFO) << "TarFileTest-begin SUB_Tar_File_SplitWriteAll_0200";
+    try {
+        vector<uint8_t> ioBuffer = {0};
+        int read = 0;
+        bool isFilled = false;
+        int ret = TarFile::GetInstance().SplitWriteAll(ioBuffer, read, isFilled);
+        EXPECT_EQ(ret, 0);
+        ClearCache();
+    } catch (...) {
+        EXPECT_TRUE(false);
+        GTEST_LOG_(INFO) << "TarFileTest-an exception occurred by TarFile.";
+    }
+    GTEST_LOG_(INFO) << "TarFileTest-end SUB_Tar_File_SplitWriteAll_0200";
+}
+
+/**
+ * @tc.number: SUB_Tar_File_SplitWriteAll_0300
+ * @tc.name: SUB_Tar_File_SplitWriteAll_0300
+ * @tc.desc: 测试 SplitWriteAll 接口
+ * @tc.size: MEDIUM
+ * @tc.type: FUNC
+ * @tc.level Level 1
+ * @tc.require: I6F3GV
+ */
+HWTEST_F(TarFileTest, SUB_Tar_File_SplitWriteAll_0300, testing::ext::TestSize.Level1)
+{
+    GTEST_LOG_(INFO) << "TarFileTest-begin SUB_Tar_File_SplitWriteAll_0300";
+    try {
+        CreateTarFile("SUB_Tar_File_SplitWriteAll_0300");
+        vector<uint8_t> ioBuffer = {0};
+        int read = 1;
+        bool isFilled = false;
+        int ret = TarFile::GetInstance().SplitWriteAll(ioBuffer, read, isFilled);
+        EXPECT_EQ(ret, 1);
+        ClearCache();
+    } catch (...) {
+        EXPECT_TRUE(false);
+        GTEST_LOG_(INFO) << "TarFileTest-an exception occurred by TarFile.";
+    }
+    GTEST_LOG_(INFO) << "TarFileTest-end SUB_Tar_File_SplitWriteAll_0300";
+}
+
+/**
+ * @tc.number: SUB_Tar_File_SplitWriteAll_0400
+ * @tc.name: SUB_Tar_File_SplitWriteAll_0400
+ * @tc.desc: 测试 SplitWriteAll 接口
+ * @tc.size: MEDIUM
+ * @tc.type: FUNC
+ * @tc.level Level 1
+ * @tc.require: I6F3GV
+ */
+HWTEST_F(TarFileTest, SUB_Tar_File_SplitWriteAll_0400, testing::ext::TestSize.Level1)
+{
+    GTEST_LOG_(INFO) << "TarFileTest-begin SUB_Tar_File_SplitWriteAll_0400";
+    try {
+        // 预置文件和目录
+        TestManager tm("SUB_Tar_File_SplitWriteAll_0400");
+        string root = tm.GetRootDirCurTest();
+        string testDir = root + "/testdir";
+        if (mkdir(testDir.data(), S_IRWXU) && errno != EEXIST) {
+            GTEST_LOG_(INFO) << " invoked mkdir failure, errno :" << errno;
+            throw BError(errno);
+        }
+        string aFile = testDir + "/a.txt";
+        string bFile = testDir + "/b.txt";
+        SaveStringToFile(aFile, "hello");
+        SaveStringToFile(bFile, "world");
+
+        string tarFile = root + "test.tar";
+        string cmd = "tar -cvf " + tarFile + " " + testDir;
+        if (system(cmd.c_str()) != 0) {
+            GTEST_LOG_(INFO) << " execute tar failure, errno :" << errno;
+            throw BError(errno);
+        }
+        TarFile::GetInstance().currentTarFile_ = fopen(tarFile.c_str(), "wb+");
+
+        vector<uint8_t> ioBuffer;
+        ioBuffer.resize(READ_BUFF_SIZE);
+        int read = READ_BUFF_SIZE;
+        bool isFilled = false;
+        int ret = TarFile::GetInstance().SplitWriteAll(ioBuffer, read, isFilled);
+        EXPECT_GT(ret, 0);
+        ClearCache();
+    } catch (...) {
+        EXPECT_TRUE(false);
+        GTEST_LOG_(INFO) << "TarFileTest-an exception occurred by TarFile.";
+    }
+    GTEST_LOG_(INFO) << "TarFileTest-end SUB_Tar_File_SplitWriteAll_0400";
+}
+
+/**
+ * @tc.number: SUB_Tar_File_CreateSplitTarFile_0100
+ * @tc.name: SUB_Tar_File_CreateSplitTarFile_0100
+ * @tc.desc: 测试 CreateSplitTarFile 接口
+ * @tc.size: MEDIUM
+ * @tc.type: FUNC
+ * @tc.level Level 1
+ * @tc.require: I6F3GV
+ */
+HWTEST_F(TarFileTest, SUB_Tar_File_CreateSplitTarFile_0100, testing::ext::TestSize.Level1)
+{
+    GTEST_LOG_(INFO) << "TarFileTest-begin SUB_Tar_File_CreateSplitTarFile_0100";
+    try {
+        bool ret = TarFile::GetInstance().CreateSplitTarFile();
+        EXPECT_FALSE(ret);
+        ClearCache();
+    } catch (...) {
+        EXPECT_TRUE(false);
+        GTEST_LOG_(INFO) << "TarFileTest-an exception occurred by TarFile.";
+    }
+    GTEST_LOG_(INFO) << "TarFileTest-end SUB_Tar_File_CreateSplitTarFile_0100";
+}
+
+/**
+ * @tc.number: SUB_Tar_File_CreateSplitTarFile_0200
+ * @tc.name: SUB_Tar_File_CreateSplitTarFile_0200
+ * @tc.desc: 测试 CreateSplitTarFile 接口
+ * @tc.size: MEDIUM
+ * @tc.type: FUNC
+ * @tc.level Level 1
+ * @tc.require: I6F3GV
+ */
+HWTEST_F(TarFileTest, SUB_Tar_File_CreateSplitTarFile_0200, testing::ext::TestSize.Level1)
+{
+    GTEST_LOG_(INFO) << "TarFileTest-begin SUB_Tar_File_CreateSplitTarFile_0200";
+    try {
+        TestManager tm("SUB_Tar_File_CreateSplitTarFile_0200");
+        string root = tm.GetRootDirCurTest();
+        TarFile::GetInstance().baseTarName_ = "test";
+        TarFile::GetInstance().packagePath_ = root;
+        bool ret = TarFile::GetInstance().CreateSplitTarFile();
+        EXPECT_TRUE(ret);
+        EXPECT_TRUE(TarFile::GetInstance().currentTarFile_ != nullptr);
+        EXPECT_EQ(TarFile::GetInstance().currentTarFileSize_, 0);
+        ClearCache();
+    } catch (...) {
+        EXPECT_TRUE(false);
+        GTEST_LOG_(INFO) << "TarFileTest-an exception occurred by TarFile.";
+    }
+    GTEST_LOG_(INFO) << "TarFileTest-end SUB_Tar_File_CreateSplitTarFile_0200";
+}
+
+/**
+ * @tc.number: SUB_Tar_File_CompleteBlock_0100
+ * @tc.name: SUB_Tar_File_CompleteBlock_0100
+ * @tc.desc: 测试 CompleteBlock 接口
+ * @tc.size: MEDIUM
+ * @tc.type: FUNC
+ * @tc.level Level 1
+ * @tc.require: I6F3GV
+ */
+HWTEST_F(TarFileTest, SUB_Tar_File_CompleteBlock_0100, testing::ext::TestSize.Level1)
+{
+    GTEST_LOG_(INFO) << "TarFileTest-begin SUB_Tar_File_CompleteBlock_0100";
+    try {
+        off_t size = 0;
+        bool ret = TarFile::GetInstance().CompleteBlock(size);
+        EXPECT_TRUE(ret);
+        ClearCache();
+    } catch (...) {
+        EXPECT_TRUE(false);
+        GTEST_LOG_(INFO) << "TarFileTest-an exception occurred by TarFile.";
+    }
+    GTEST_LOG_(INFO) << "TarFileTest-end SUB_Tar_File_CompleteBlock_0100";
+}