diff --git a/CMakeLists.txt b/CMakeLists.txt
index c7157bc3..1c61653f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,16 +1,11 @@
 cmake_minimum_required(VERSION 3.0)
 project(GmSSL)
 
+set(LIBRARY_OUTPUT_PATH ${PROJECT_BINARY_DIR}/lib)
+set(EXECUTABLE_OUTPUT_PATH ${PROJECT_BINARY_DIR}/bin)
 
-if (WIN32)
-	set(LIBRARY_OUTPUT_PATH ${PROJECT_BINARY_DIR}/bin)
-	set(EXECUTABLE_OUTPUT_PATH ${PROJECT_BINARY_DIR}/bin)
-else()
-	set(LIBRARY_OUTPUT_PATH ${PROJECT_BINARY_DIR}/lib)
-	set(EXECUTABLE_OUTPUT_PATH ${PROJECT_BINARY_DIR}/bin)
-endif()
+option(BUILD_SHARED_LIBS "Build using shared libraries" ON)
 
-option(BUILD_SHARED_LIBS "Build using shared libraries" OFF)
 include_directories(include)
 
 #enable_language(ASM)
@@ -39,7 +34,6 @@ set(src
 	src/sha256.c
 	src/sha512.c
 	src/chacha20.c
-	src/rand.c
 	src/hash_drbg.c
 	src/block_cipher.c
 	src/digest.c
@@ -84,6 +78,9 @@ set(src
 
 if (WIN32)
 	list(APPEND src src/u_time.c)
+	list(APPEND src src/rand_win.c)
+else()
+	list(APPEND src src/rand.c)
 endif()
 
 set(broken_crypto_src
diff --git a/src/rand_win.c b/src/rand_win.c
new file mode 100644
index 00000000..01f0785d
--- /dev/null
+++ b/src/rand_win.c
@@ -0,0 +1,47 @@
+/*
+ *  Copyright 2014-2022 The GmSSL Project. All Rights Reserved.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the License); you may
+ *  not use this file except in compliance with the License.
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ */
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <wincrypt.h>
+#include <gmssl/error.h>
+
+
+int rand_bytes(uint8_t *buf, size_t len)
+{
+	HCRYPTPROV hCryptProv = NULL;
+	int ret = -1;
+
+	if (!buf) {
+		error_print();
+		return -1;
+	}
+	if (len > INT_MAX) {
+		error_print();
+		return -1;
+	}
+	if (CryptAcquireContextA(&hCryptProv, NULL, NULL, PROV_RSA_FULL,
+		CRYPT_VERIFYCONTEXT|CRYPT_SILENT) != TRUE) {
+		error_print();
+		return -1;
+	}
+	if (CryptGenRandom(hCryptProv, (DWORD)len, buf) != TRUE) {
+		error_print();
+		goto end;
+	}
+	ret = 1
+end:
+	if (CryptReleaseContext(hCryptProv, 0) != TRUE) {
+		error_print();
+		ret = -1;
+	}
+	return ret;
+}