diff --git a/libavcodec/ac3enc.c b/libavcodec/ac3enc.c
index 107fe937f9..647d815899 100644
--- a/libavcodec/ac3enc.c
+++ b/libavcodec/ac3enc.c
@@ -1609,7 +1609,6 @@ static av_cold int ac3_encode_init(AVCodecContext *avctx)
     mdct_init(9);
 
     avctx->coded_frame= avcodec_alloc_frame();
-    avctx->coded_frame->key_frame= 1;
 
     return 0;
 }