diff --git a/rdagent/scenarios/qlib/factor_experiment_loader/json_loader.py b/rdagent/scenarios/qlib/factor_experiment_loader/json_loader.py
index a6558e2cb..0f028c294 100644
--- a/rdagent/scenarios/qlib/factor_experiment_loader/json_loader.py
+++ b/rdagent/scenarios/qlib/factor_experiment_loader/json_loader.py
@@ -30,7 +30,7 @@ def load(self, factor_dict: dict) -> QlibFactorExperiment:
 
 class FactorExperimentLoaderFromJsonFile(FactorExperimentLoader):
     def load(self, json_file_path: Path) -> list:
-        with open(json_file_path, "r") as file:
+        with open(json_file_path, "r", encoding="utf-8") as file:
             factor_dict = json.load(file)
         return FactorExperimentLoaderFromDict().load(factor_dict)
 
@@ -45,7 +45,7 @@ def load(self, json_string: str) -> list:
 # class FactorTestCaseLoaderFromJsonFile(Loader[TestCases]):
 class FactorTestCaseLoaderFromJsonFile:
     def load(self, json_file_path: Path) -> TestCases:
-        with open(json_file_path, "r") as file:
+        with open(json_file_path, "r", encoding="utf-8") as file:
             factor_dict = json.load(file)
         test_cases = TestCases()
         for factor_name, factor_data in factor_dict.items():