diff --git a/python/paddle/optimizer/lr.py b/python/paddle/optimizer/lr.py
index 258e69978a2ec6872cfea4975933d80386a2570a..07420be8915d3b1b7051b09958f55f7d3c30d3a8 100644
--- a/python/paddle/optimizer/lr.py
+++ b/python/paddle/optimizer/lr.py
@@ -1406,7 +1406,7 @@ class ReduceOnPlateau(LRScheduler):
             metrics, (int, float, numpy.float32, numpy.float64)
         ):
             raise TypeError(
-                "metrics must be 'int', 'float', 'np.float', 'numpy.ndarray' or 'paddle.Tensor', but receive {}".format(
+                "metrics must be 'int', 'float', 'np.float64', 'numpy.ndarray' or 'paddle.Tensor', but receive {}".format(
                     type(metrics)
                 )
             )