diff --git a/httprunner/__init__.py b/httprunner/__init__.py
index db07b46c..dd499f47 100644
--- a/httprunner/__init__.py
+++ b/httprunner/__init__.py
@@ -1 +1 @@
-__version__ = '0.8.5'
\ No newline at end of file
+__version__ = '0.8.6'
\ No newline at end of file
diff --git a/httprunner/locusts.py b/httprunner/locusts.py
index 11ade7a2..5611efb2 100644
--- a/httprunner/locusts.py
+++ b/httprunner/locusts.py
@@ -1,4 +1,4 @@
-import codecs
+import io
 import multiprocessing
 import os
 import sys
@@ -39,8 +39,8 @@ def gen_locustfile(testcase_file_path):
     testset = load_test_file(testcase_file_path)
     host = testset.get("config", {}).get("request", {}).get("base_url", "")
 
-    with codecs.open(template_path, encoding='utf-8') as template:
-        with codecs.open(locustfile_path, 'w', encoding='utf-8') as locustfile:
+    with io.open(template_path, encoding='utf-8') as template:
+        with io.open(locustfile_path, 'w', encoding='utf-8') as locustfile:
             template_content = template.read()
             template_content = template_content.replace("$HOST", host)
             template_content = template_content.replace("$TESTCASE_FILE", testcase_file_path)
diff --git a/httprunner/testcase.py b/httprunner/testcase.py
index 9652d412..c83204ac 100644
--- a/httprunner/testcase.py
+++ b/httprunner/testcase.py
@@ -1,5 +1,5 @@
 import ast
-import codecs
+import io
 import json
 import logging
 import os
@@ -22,7 +22,7 @@ testcases_cache_mapping = {}
 def _load_yaml_file(yaml_file):
     """ load yaml file and check file content format
     """
-    with codecs.open(yaml_file, 'r', encoding='utf-8') as stream:
+    with io.open(yaml_file, 'r', encoding='utf-8') as stream:
         yaml_content = yaml.load(stream)
         check_format(yaml_file, yaml_content)
         return yaml_content
@@ -30,7 +30,7 @@ def _load_yaml_file(yaml_file):
 def _load_json_file(json_file):
     """ load json file and check file content format
     """
-    with codecs.open(json_file, encoding='utf-8') as data_file:
+    with io.open(json_file, encoding='utf-8') as data_file:
         try:
             json_content = json.load(data_file)
         except exception.JSONDecodeError: