diff --git a/interfaces/innerkits/unwinder/include/dfx_map.h b/interfaces/innerkits/unwinder/include/dfx_map.h
index 685670d149ca76857cbb403dbef5bc2953abe49c..f220f4aa9a92b54550c9a12f3f312c63ff2588f3 100644
--- a/interfaces/innerkits/unwinder/include/dfx_map.h
+++ b/interfaces/innerkits/unwinder/include/dfx_map.h
@@ -29,7 +29,7 @@ class DfxHap;
 
 class DfxMap {
 public:
-    static std::shared_ptr<DfxMap> Create(std::string buf, size_t size);
+    static std::shared_ptr<DfxMap> Create(const std::string& vma);
     static void PermsToProts(const std::string perms, uint32_t& prots, uint32_t& flag);
     static void FormatMapName(pid_t pid, std::string& mapName);
     static std::string UnFormatMapName(const std::string& mapName);
@@ -42,7 +42,7 @@ public:
         uint32_t prots, const std::string& name)
         : begin(begin), end(end), offset(offset), prots(prots), name(name) {}
 
-    bool Parse(char* buf, size_t size);
+    bool Parse(const char* buf, size_t size);
     bool IsMapExec();
     bool IsArkExecutable();
     bool IsJsvmExecutable();
diff --git a/interfaces/innerkits/unwinder/src/maps/dfx_map.cpp b/interfaces/innerkits/unwinder/src/maps/dfx_map.cpp
index 92af99a1e566fcb34475b60298c7fb11db9e9dea..57ad90f230e506723f26f27d9b56566c80e37902 100644
--- a/interfaces/innerkits/unwinder/src/maps/dfx_map.cpp
+++ b/interfaces/innerkits/unwinder/src/maps/dfx_map.cpp
@@ -192,20 +192,20 @@ AT_ALWAYS_INLINE bool PermsToProtsAndFlag(const char* permChs, const size_t sz,
 #endif
 }
 
-std::shared_ptr<DfxMap> DfxMap::Create(std::string buf, size_t size)
+std::shared_ptr<DfxMap> DfxMap::Create(const std::string& vma)
 {
-    if (buf.empty() || size == 0) {
+    if (vma.empty()) {
         return nullptr;
     }
     auto map = std::make_shared<DfxMap>();
-    if (!map->Parse(&buf[0], size)) {
-        DFXLOGW("Failed to parse map: %{public}s", buf.c_str());
+    if (!map->Parse(vma.c_str(), vma.size())) {
+        DFXLOGW("Failed to parse map: %{public}s", vma.c_str());
         return nullptr;
     }
     return map;
 }
 
-bool DfxMap::Parse(char* buf, size_t size)
+bool DfxMap::Parse(const char* buf, size_t size)
 {
 #if defined(is_ohos) && is_ohos
     if (buf == nullptr || size == 0) {
diff --git a/test/unittest/unwind/maps_test.cpp b/test/unittest/unwind/maps_test.cpp
index 057a73313a11678c11138d1f6f2b41fc77a4310d..045c0fbf7c0b9ab9e4bec28e6617f2f43a2038f2 100644
--- a/test/unittest/unwind/maps_test.cpp
+++ b/test/unittest/unwind/maps_test.cpp
@@ -166,7 +166,7 @@ HWTEST_F(MapsTest, GetRelPcTest, TestSize.Level2)
     uint64_t pc = 0x7f0ab40016;
     const uint64_t invalidOffset = 0x16;
 #endif
-    shared_ptr<DfxMap> map = DfxMap::Create(INVALID_MAP_ITEM, sizeof(INVALID_MAP_ITEM));
+    shared_ptr<DfxMap> map = DfxMap::Create(INVALID_MAP_ITEM);
     EXPECT_EQ(true, ((map->GetElf() == nullptr) && (map->GetRelPc(pc) == invalidOffset)));
     GTEST_LOG_(INFO) << "GetRelPcTest: end.";
 }
@@ -179,7 +179,7 @@ HWTEST_F(MapsTest, GetRelPcTest, TestSize.Level2)
 HWTEST_F(MapsTest, ToStringTest, TestSize.Level2)
 {
     GTEST_LOG_(INFO) << "ToStringTest: start.";
-    shared_ptr<DfxMap> map = DfxMap::Create(VALID_MAP_ITEM, sizeof(VALID_MAP_ITEM));
+    shared_ptr<DfxMap> map = DfxMap::Create(VALID_MAP_ITEM);
     GTEST_LOG_(INFO) << map->ToString();
     EXPECT_EQ(true, sizeof(map->ToString()) != 0);
     GTEST_LOG_(INFO) << "ToStringTest: end.";
@@ -257,7 +257,7 @@ HWTEST_F(MapsTest, IsArkExecutedMapTest, TestSize.Level2)
 HWTEST_F(MapsTest, IsVdsoMapTest, TestSize.Level2)
 {
     GTEST_LOG_(INFO) << "IsVdsoMapTest: start.";
-    shared_ptr<DfxMap> map = DfxMap::Create(VDSO_MAP_ITEM, VDSO_MAP_ITEM.size());
+    shared_ptr<DfxMap> map = DfxMap::Create(VDSO_MAP_ITEM);
     ASSERT_TRUE(map->IsVdsoMap());
     GTEST_LOG_(INFO) << "IsVdsoMapTest: end.";
 }
diff --git a/test/unittest/unwind/unwinder_test.cpp b/test/unittest/unwind/unwinder_test.cpp
index 405ef38bc091209e5e5167ba3560d01b6b5aff52..b61922361b60f7892eb1ccb5ffbfa0d39cff5d74 100644
--- a/test/unittest/unwind/unwinder_test.cpp
+++ b/test/unittest/unwind/unwinder_test.cpp
@@ -648,7 +648,7 @@ HWTEST_F(UnwinderTest, FillFrameTest001, TestSize.Level2)
     GTEST_LOG_(INFO) << " when DfxFrame::map is null, frame.buildId.size() is 0";
     ASSERT_EQ(frame.buildId.size(), 0);
     string testMap = "f6d83000-f6d84000 r--p 00001000 b3:07 1892 /system/lib/init/libinit_context.z.so.noexit";
-    auto map = DfxMap::Create(testMap, testMap.size());
+    auto map = DfxMap::Create(testMap);
     frame.map = map;
     unwinder->FillFrame(frame);
     GTEST_LOG_(INFO) << " when DfxFrame::map is not null and file not exist, frame.buildId.size() is 0";
@@ -658,7 +658,7 @@ HWTEST_F(UnwinderTest, FillFrameTest001, TestSize.Level2)
 #else
     testMap = "7f0ab40000-7f0ab41000 r--p 00000000 b3:07 1882 /system/lib64/init/libinit_context.z.so";
 #endif
-    map = DfxMap::Create(testMap, testMap.size());
+    map = DfxMap::Create(testMap);
     frame.map = map;
     unwinder->FillFrame(frame);
     GTEST_LOG_(INFO) << " when DfxFrame::map is not null and file exist, frame.buildId.size() is bigger than 0";
@@ -681,7 +681,7 @@ HWTEST_F(UnwinderTest, FillJsFrameTest001, TestSize.Level2)
     GTEST_LOG_(INFO) << " when DfxFrame::map is null, frame.map is nullptr";
     ASSERT_EQ(frame.map, nullptr);
     string testMap = "f6d83000-f6d84000 r--p 00001000 b3:07 1892 /system/lib/init/libinit_context.z.so";
-    auto map = DfxMap::Create(testMap, testMap.size());
+    auto map = DfxMap::Create(testMap);
     frame.map = map;
     unwinder->FillJsFrame(frame);
     GTEST_LOG_(INFO) << " when DfxFrame::map is not null and file exist, frame.map.GetHap is not nullptr";
@@ -706,7 +706,7 @@ HWTEST_F(UnwinderTest, FillFramesTest001, TestSize.Level2)
     auto unwinder = std::make_shared<Unwinder>();
     std::vector<DfxFrame> frames;
     DfxFrame frame;
-    auto map = DfxMap::Create(testMap, testMap.size());
+    auto map = DfxMap::Create(testMap);
     frame.map = map;
     frames.push_back(frame);
     ASSERT_EQ(frames[0].buildId.size(), 0);