diff --git a/ppocr/modeling/heads/rec_sar_head.py b/ppocr/modeling/heads/rec_sar_head.py
index 3c131c8b5dfad74cf179b74e7556a70befd7f12d..647f58200f83e3f2c23030872c606f299c58f7b7 100644
--- a/ppocr/modeling/heads/rec_sar_head.py
+++ b/ppocr/modeling/heads/rec_sar_head.py
@@ -195,7 +195,7 @@ class ParallelSARDecoder(BaseDecoder):
 
         # Prediction layer
         self.pred_dropout = nn.Dropout(pred_dropout)
-        pred_num_classes = num_classes - 1
+        pred_num_classes = self.num_classes - 1
         if pred_concat:
             fc_in_channel = decoder_rnn_out_size + d_model + d_enc
         else: