diff --git a/ppdet/slim/distill.py b/ppdet/slim/distill.py
index 996342e154686ba152fe8319755a17ac8b36c918..a20c93a31e0810aa8c5956c5444e4ba449357a8a 100644
--- a/ppdet/slim/distill.py
+++ b/ppdet/slim/distill.py
@@ -262,7 +262,7 @@ class FGDFeatureLoss(nn.Layer):
         zeros_init = parameter_init("constant", 0.0)
 
         if student_channels != teacher_channels:
-            self.align = nn.Conv2d(
+            self.align = nn.Conv2D(
                 student_channels,
                 teacher_channels,
                 kernel_size=1,