diff --git a/base/test/fuzztest/BUILD.gn b/base/test/fuzztest/BUILD.gn
index 61243ac948c902c7337294755121eddbd931b952..97ca64680145194de07b4254820f05377b3c7d80 100644
--- a/base/test/fuzztest/BUILD.gn
+++ b/base/test/fuzztest/BUILD.gn
@@ -20,6 +20,7 @@ group("fuzztest") {
     # deps file
     "parcel_fuzzer:ParcelFuzzTest",
     "refbase_fuzzer:RefbaseFuzzTest",
+    "string_fuzzer:StringFuzzTest",
     "timer_fuzzer:TimerFuzzTest",
   ]
 }
diff --git a/base/test/fuzztest/string_fuzzer/BUILD.gn b/base/test/fuzztest/string_fuzzer/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..758e4499ef84081f170705f241236408c60312b3
--- /dev/null
+++ b/base/test/fuzztest/string_fuzzer/BUILD.gn
@@ -0,0 +1,33 @@
+# Copyright (c) 2024 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.
+import("//build/test.gni")
+
+##############################fuzztest##########################################
+ohos_fuzztest("StringFuzzTest") {
+  module_out_path = "c_utils/c_utils"
+  fuzz_config_file = "."
+  include_dirs = [ "../" ]
+  cflags = [
+    "-g",
+    "-O0",
+    "-Wno-unused-variable",
+    "-fno-omit-frame-pointer",
+  ]
+  defines = [ "DEBUG_FUZZ" ]
+  external_deps = [
+    "c_utils:utils",
+    "hilog:libhilog_base",
+  ]
+  sources = [ "string_fuzzer.cpp" ]
+}
+###############################################################################
diff --git a/base/test/fuzztest/string_fuzzer/corpus/init b/base/test/fuzztest/string_fuzzer/corpus/init
new file mode 100644
index 0000000000000000000000000000000000000000..e7c3fecd8d4d4816e40088113a2316bb9eb2e13f
--- /dev/null
+++ b/base/test/fuzztest/string_fuzzer/corpus/init
@@ -0,0 +1,14 @@
+# Copyright (c) 2024 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.
+
+FUZZ
\ No newline at end of file
diff --git a/base/test/fuzztest/string_fuzzer/project.xml b/base/test/fuzztest/string_fuzzer/project.xml
new file mode 100644
index 0000000000000000000000000000000000000000..d6679ccc2ec868b072c934ed45102d545f31f91d
--- /dev/null
+++ b/base/test/fuzztest/string_fuzzer/project.xml
@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) 2024 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.
+
+-->
+<fuzz_config>
+  <fuzztest>
+    <!-- maximum length of a test input -->
+    <max_len>1000</max_len>
+    <!-- maximum total time in seconds to run the fuzzer -->
+    <max_total_time>300</max_total_time>
+    <!-- memory usage limit in Mb -->
+    <rss_limit_mb>4096</rss_limit_mb>
+  </fuzztest>
+</fuzz_config>
diff --git a/base/test/fuzztest/string_fuzzer/string_fuzzer.cpp b/base/test/fuzztest/string_fuzzer/string_fuzzer.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..3f7fab098b24f6fa93dfb0b82bd4db8b236cbb7f
--- /dev/null
+++ b/base/test/fuzztest/string_fuzzer/string_fuzzer.cpp
@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 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.
+ */
+
+#include "string_fuzzer.h"
+
+#include <cstdint>
+#include <thread>
+#include <vector>
+
+#include "fuzz_log.h"
+#include "fuzzer/FuzzedDataProvider.h"
+#include "string_ex.h"
+
+using namespace std;
+
+namespace OHOS {
+const uint8_t MAX_STRING_LENGTH = 255;
+
+void StringTestFunc(FuzzedDataProvider* dataProvider)
+{
+    FUZZ_LOGI("StringTestFunc start");
+    string str = dataProvider->ConsumeRandomLengthString(MAX_STRING_LENGTH);
+    string src = dataProvider->ConsumeRandomLengthString(MAX_STRING_LENGTH);
+    string dst = dataProvider->ConsumeRandomLengthString(MAX_STRING_LENGTH);
+    ReplaceStr(str, src, dst);
+
+    int value = dataProvider->ConsumeIntegral<int>();
+    bool upper = dataProvider->ConsumeBool();
+    DexToHexString(value, upper);
+
+    string newStr = dataProvider->ConsumeRandomLengthString(MAX_STRING_LENGTH);
+    IsAlphaStr(newStr);
+    IsUpperStr(newStr);
+    IsLowerStr(newStr);
+    IsNumericStr(newStr);
+
+    string sub = dataProvider->ConsumeRandomLengthString(MAX_STRING_LENGTH);
+    IsSubStr(newStr, sub);
+
+    string left = dataProvider->ConsumeRandomLengthString(MAX_STRING_LENGTH);
+    string right = dataProvider->ConsumeRandomLengthString(MAX_STRING_LENGTH);
+    string emptySubStr;
+    GetFirstSubStrBetween(newStr, left, right, emptySubStr);
+    FUZZ_LOGI("StringTestFunc end");
+}
+} // namespace OHOS
+
+/* Fuzzer entry point */
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size)
+{
+    FuzzedDataProvider dataProvider(data, size);
+    OHOS::StringTestFunc(&dataProvider);
+    return 0;
+}
diff --git a/base/test/fuzztest/string_fuzzer/string_fuzzer.h b/base/test/fuzztest/string_fuzzer/string_fuzzer.h
new file mode 100644
index 0000000000000000000000000000000000000000..cdb04a89b66768cd37c8792b717883cd7da66edb
--- /dev/null
+++ b/base/test/fuzztest/string_fuzzer/string_fuzzer.h
@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2024 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.
+ */
+
+#ifndef STRING_FUZZER_H
+#define STRING_FUZZER_H
+
+#define FUZZ_PROJECT_NAME "string_fuzzer"
+
+#endif // STRING_FUZZER_H