diff --git a/source/api_cc/tests/test_read_file_to_string.cc b/source/api_cc/tests/test_read_file_to_string.cc
index 2aa6be7e6f..b4ceda5598 100644
--- a/source/api_cc/tests/test_read_file_to_string.cc
+++ b/source/api_cc/tests/test_read_file_to_string.cc
@@ -12,11 +12,8 @@
 
 #include "common.h"
 TEST(TestReadFileToString, readfiletostring) {
-  std::string file_name = "../../tests/infer/deeppot.pbtxt";
-  deepmd::convert_pbtxt_to_pb(file_name, "deeppot.pb");
   std::string file_content;
-  deepmd::read_file_to_string("deeppot.pb", file_content);
-  remove("deeppot.pb");
+  deepmd::read_file_to_string("../../tests/infer/deeppot.txt", file_content);
 
   std::string file_name_2 = "../../tests/infer/deeppot.txt";
   std::stringstream buffer;