diff --git a/python/ray/train/xgboost/xgboost_checkpoint.py b/python/ray/train/xgboost/xgboost_checkpoint.py
index 447fb1e32f8e..2c6fbaeb0abf 100644
--- a/python/ray/train/xgboost/xgboost_checkpoint.py
+++ b/python/ray/train/xgboost/xgboost_checkpoint.py
@@ -15,7 +15,7 @@
 class XGBoostCheckpoint(FrameworkCheckpoint):
     """A :py:class:`~ray.train.Checkpoint` with XGBoost-specific functionality."""
 
-    MODEL_FILENAME = "model.json"
+    MODEL_FILENAME = "model.ubj"
 
     @classmethod
     def from_model(