diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index aa9fca22..46d791c1 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -10,6 +10,7 @@
 **Fixed**
 
 - fix: ensure upload ready
+- fix: add ExtendJSONEncoder to safely dump json data with python object, such as MultipartEncoder
 
 ## 3.0.9 (2020-06-07)
 
diff --git a/httprunner/compat.py b/httprunner/compat.py
index 35b996f9..20c442f4 100644
--- a/httprunner/compat.py
+++ b/httprunner/compat.py
@@ -264,7 +264,7 @@ import time
 import pytest
 from loguru import logger
 
-from httprunner.utils import get_platform
+from httprunner.utils import get_platform, ExtendJSONEncoder
 
 
 @pytest.fixture(scope="session", autouse=True)
@@ -316,7 +316,7 @@ def session_fixture(request):
     os.makedirs(summary_dir, exist_ok=True)
 
     with open(summary_path, "w", encoding="utf-8") as f:
-        json.dump(summary, f, indent=4)
+        json.dump(summary, f, indent=4, ensure_ascii=False, cls=ExtendJSONEncoder)
 
     logger.info(f"generated task summary: {summary_path}")
 
diff --git a/httprunner/utils.py b/httprunner/utils.py
index 02d9b127..117dfbbd 100644
--- a/httprunner/utils.py
+++ b/httprunner/utils.py
@@ -212,3 +212,14 @@ def ensure_file_path_valid(file_path: Text) -> Text:
 
     new_file_path = os.path.join(os.getcwd(), f"{os.sep.join(path_names)}{file_suffix}")
     return new_file_path
+
+
+class ExtendJSONEncoder(json.JSONEncoder):
+    """ especially used to safely dump json data with python object, such as MultipartEncoder
+    """
+
+    def default(self, obj):
+        try:
+            return super(ExtendJSONEncoder, self).default(obj)
+        except (UnicodeDecodeError, TypeError):
+            return repr(obj)
diff --git a/tests/utils_test.py b/tests/utils_test.py
index b15a5c7f..9903c1d9 100644
--- a/tests/utils_test.py
+++ b/tests/utils_test.py
@@ -1,8 +1,10 @@
+import decimal
+import json
 import os
 import unittest
 
 from httprunner import loader, utils
-from httprunner.utils import ensure_file_path_valid
+from httprunner.utils import ensure_file_path_valid, ExtendJSONEncoder
 
 
 class TestUtils(unittest.TestCase):
@@ -116,3 +118,14 @@ class TestUtils(unittest.TestCase):
             ensure_file_path_valid("examples/postman_echo/request_methods/"),
             os.path.join(os.getcwd(), "examples/postman_echo/request_methods"),
         )
+
+    def test_safe_dump_json(self):
+        class A(object):
+            pass
+
+        data = {"a": A(), "b": decimal.Decimal("1.45")}
+
+        with self.assertRaises(TypeError):
+            json.dumps(data)
+
+        json.dumps(data, cls=ExtendJSONEncoder)