diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index acf41ab2..7a6ca243 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -1,6 +1,6 @@
 # Release History
 
-## 2.4.9 (2019-12-25)
+## 2.4.9 (2019-12-26)
 
 **Added**
 
@@ -9,6 +9,7 @@
 **Fixed**
 
 - fix: display validators in report when validate raised exception
+- fix: eval validator python script before validating
 
 ## 2.4.8 (2019-12-25)
 
diff --git a/httprunner/validator.py b/httprunner/validator.py
index 3a821047..8dad5ac6 100644
--- a/httprunner/validator.py
+++ b/httprunner/validator.py
@@ -124,7 +124,8 @@ except Exception as ex:
         for validator in validators:
 
             if isinstance(validator, dict) and validator.get("type") == "python_script":
-                validator_dict, ex = self.validate_script(validator["script"])
+                script = self.session_context.eval_content(validator["script"])
+                validator_dict, ex = self.validate_script(script)
                 if ex:
                     validate_pass = False
                     failures.append(ex)