diff --git a/src/entry/Maat_rule.cpp b/src/entry/Maat_rule.cpp
index 8bc5366..4c557fa 100644
--- a/src/entry/Maat_rule.cpp
+++ b/src/entry/Maat_rule.cpp
@@ -26,7 +26,7 @@
 #include "mesa_fuzzy.h"
 #include "great_index_engine.h"
 
-int MAAT_FRAME_VERSION_1_8_20160623_PERF_TEST=1;
+int MAAT_FRAME_VERSION_1_8_20160624_PERF_TEST=1;
 const char *maat_module="MAAT Frame";
 
 const char* CHARSET_STRING[]={"NONE","gbk","big5","unicode","utf8","bin",
@@ -810,6 +810,7 @@ struct op_expr_t* create_op_expr(unsigned int expr_id,int operation,void* u_para
 	struct op_expr_t* op_expr=NULL;
 	op_expr=(struct op_expr_t*)calloc(sizeof(struct op_expr_t),1);
 	op_expr->no_effect_convert_cnt=0;
+	op_expr->convert_failed=0;
 	op_expr->p_expr=(boolean_expr_t*)calloc(sizeof(boolean_expr_t),1);
 	op_expr->p_expr->expr_id=expr_id;
 	op_expr->p_expr->operation=operation;
@@ -1536,7 +1537,8 @@ int add_expr_rule(struct _Maat_table_info_t* table,struct db_str_rule_t* db_rule
 																					,CHARSET_STRING[table->src_charset]
 																					,CHARSET_STRING[dst_charset]);
 						free(region_string);
-						continue;
+						op_expr->convert_failed++;
+						break;
 					}
 					if(region_str_len==(int)strlen(sub_key_array[k])&&
 						0==memcmp(sub_key_array[k],region_string,region_str_len))
@@ -1561,7 +1563,9 @@ int add_expr_rule(struct _Maat_table_info_t* table,struct db_str_rule_t* db_rule
 				region_string=NULL;
 			}
 			//if each sub string's convert take no effect and src charset is one of the dst.
-			if(TRUE==table->src_charset_in_dst&&op_expr->no_effect_convert_cnt==sub_expr_cnt)
+			//if any sub expr convert failed
+			if((TRUE==table->src_charset_in_dst&&op_expr->no_effect_convert_cnt==sub_expr_cnt)||
+				op_expr->convert_failed>0)
 			{
 				destroy_op_expr(op_expr);
 				op_expr=NULL;
diff --git a/src/entry/Maat_rule_internal.h b/src/entry/Maat_rule_internal.h
index 2efa83e..b8ad00d 100644
--- a/src/entry/Maat_rule_internal.h
+++ b/src/entry/Maat_rule_internal.h
@@ -167,6 +167,7 @@ struct op_expr_t
 {
 	boolean_expr_t* p_expr;
 	scan_rule_t* p_rules[MAAT_MAX_EXPR_ITEM_NUM];
+	int convert_failed;
 	int no_effect_convert_cnt;
 };