diff --git a/lib/nghttp2_frame.h b/lib/nghttp2_frame.h
index 615bbf31..4b9222ac 100644
--- a/lib/nghttp2_frame.h
+++ b/lib/nghttp2_frame.h
@@ -57,7 +57,7 @@
 
 /* Maximum headers block size to send, calculated using
    nghttp2_hd_deflate_bound().  This is the default value, and can be
-   overridden by nghttp2_option_set_max_send_header_block_size(). */
+   overridden by nghttp2_option_set_max_send_header_block_length(). */
 #define NGHTTP2_MAX_HEADERSLEN 65536
 
 /* The number of bytes for each SETTINGS entry */