diff --git a/core/dbt/contracts/project.py b/core/dbt/contracts/project.py
index 1252564ac43..ca6b744aa71 100644
--- a/core/dbt/contracts/project.py
+++ b/core/dbt/contracts/project.py
@@ -231,7 +231,7 @@ class UserConfig(ExtensibleDbtClassMixin, Replaceable, UserConfigContract):
     printer_width: Optional[int] = None
     write_json: Optional[bool] = None
     warn_error: Optional[bool] = None
-    log_format: Optional[bool] = None
+    log_format: Optional[str] = None
     debug: Optional[bool] = None
     version_check: Optional[bool] = None
     fail_fast: Optional[bool] = None