diff --git a/libavformat/ivfenc.c b/libavformat/ivfenc.c
index 5700f01d3c..1d76c5c7cb 100644
--- a/libavformat/ivfenc.c
+++ b/libavformat/ivfenc.c
@@ -38,7 +38,7 @@ static int ivf_write_header(AVFormatContext *s)
     avio_write(pb, "DKIF", 4);
     avio_wl16(pb, 0); // version
     avio_wl16(pb, 32); // header length
-    avio_wl32(pb, ctx->codec_tag ? ctx->codec_tag : AV_RL32("VP80"));
+    avio_wl32(pb, ctx->codec_tag ? ctx->codec_tag : ctx->codec_id == AV_CODEC_ID_VP9 ? AV_RL32("VP90") : AV_RL32("VP80"));
     avio_wl16(pb, ctx->width);
     avio_wl16(pb, ctx->height);
     avio_wl32(pb, s->streams[0]->time_base.den);