diff --git a/paddle/fluid/platform/flags.cc b/paddle/fluid/platform/flags.cc
index bcf4bd9e2f6d455ef350e69c8d3fc9b5a23febd3..1f16ce335778849bb3164e989592cf294bae5ad5 100644
--- a/paddle/fluid/platform/flags.cc
+++ b/paddle/fluid/platform/flags.cc
@@ -303,7 +303,7 @@ DEFINE_double(memory_fraction_of_eager_deletion, 1.0,
  * Allocator related FLAG
  * Name: FLAGS_allocator_strategy
  * Since Version: 1.2
- * Value Range: string, {naive_best_fit, auto_growth}, default=naive_best_fit
+ * Value Range: string, {naive_best_fit, auto_growth}, default=auto_growth
  * Example:
  * Note: For selecting allocator policy of PaddlePaddle.
  */