diff --git a/HISTORY b/HISTORY
index 865427d..dc410f8 100644
--- a/HISTORY
+++ b/HISTORY
@@ -1,9 +1,10 @@
 
-Version 1.22  2015-10-09
+Version 1.22  2015-10-10
   * export php function: fastcommon_get_first_local_ip
   * add function is_private_ip
   * add function get_next_local_ip
   * export php function: fastcommon_get_next_local_ip
+  * export php function: fastcommon_is_private_ip
 
 Version 1.21  2015-09-14
   * ini_file_reader support annotation function
diff --git a/php-fastcommon/fastcommon.c b/php-fastcommon/fastcommon.c
index e932a02..b5df63e 100644
--- a/php-fastcommon/fastcommon.c
+++ b/php-fastcommon/fastcommon.c
@@ -44,6 +44,7 @@ const zend_fcall_info empty_fcall_info = { 0, NULL, NULL, NULL, NULL, 0, NULL, N
 		ZEND_FE(fastcommon_get_line_distance_km, NULL)
 		ZEND_FE(fastcommon_get_first_local_ip, NULL)
 		ZEND_FE(fastcommon_get_next_local_ip, NULL)
+		ZEND_FE(fastcommon_is_private_ip, NULL)
 		{NULL, NULL, NULL}  /* Must be the last line */
 	};
 
@@ -335,3 +336,32 @@ ZEND_FUNCTION(fastcommon_get_next_local_ip)
 	RETURN_STRING(next_ip , 1);
 }
 
+/*
+string fastcommon_is_private_ip(string ip)
+return true for private ip, otherwise false
+*/
+ZEND_FUNCTION(fastcommon_is_private_ip)
+{
+	int argc;
+    int ip_len;
+    char *ip;
+
+	argc = ZEND_NUM_ARGS();
+	if (argc != 1) {
+		logError("file: "__FILE__", line: %d, "
+			"fastcommon_is_private_ip parameters count: %d is invalid",
+			__LINE__, argc);
+		RETURN_BOOL(false);
+	}
+
+	if (zend_parse_parameters(argc TSRMLS_CC, "s", &ip,
+                &ip_len) == FAILURE)
+	{
+		logError("file: "__FILE__", line: %d, "
+			"zend_parse_parameters fail!", __LINE__);
+		RETURN_BOOL(false);
+	}
+
+    RETURN_BOOL(is_private_ip(ip));
+}
+
diff --git a/php-fastcommon/fastcommon.h b/php-fastcommon/fastcommon.h
index bb7f6ae..8458c3d 100644
--- a/php-fastcommon/fastcommon.h
+++ b/php-fastcommon/fastcommon.h
@@ -24,6 +24,7 @@ ZEND_FUNCTION(fastcommon_simple_hash);
 ZEND_FUNCTION(fastcommon_get_line_distance_km);
 ZEND_FUNCTION(fastcommon_get_first_local_ip);
 ZEND_FUNCTION(fastcommon_get_next_local_ip);
+ZEND_FUNCTION(fastcommon_is_private_ip);
 
 #ifdef __cplusplus
 }