diff --git a/configure.ac b/configure.ac
index f93a3deaa..71b9f5bf7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2835,9 +2835,9 @@ if test X"$want_nghttp2" != Xno; then
   CPPFLAGS="$CPPFLAGS $CPP_H2"
   LIBS="$LIB_H2 $LIBS"
 
-  # use nghttp2_session_set_local_window_size to require nghttp2
-  # >= 1.12.0
-  AC_CHECK_LIB(nghttp2, nghttp2_session_set_local_window_size,
+  # use nghttp2_session_get_stream_local_window_size to require nghttp2
+  # >= 1.15.0
+  AC_CHECK_LIB(nghttp2, nghttp2_session_get_stream_local_window_size,
     [
      AC_CHECK_HEADERS(nghttp2/nghttp2.h,
         curl_h2_msg="enabled (nghttp2)"
diff --git a/docs/INTERNALS.md b/docs/INTERNALS.md
index 0737044a7..cd8cc8fe2 100644
--- a/docs/INTERNALS.md
+++ b/docs/INTERNALS.md
@@ -30,7 +30,7 @@ versions of libs and build tools.
  - GSKit        V5R3M0
  - NSS          3.14.x
  - Heimdal      ?
- - nghttp2      1.12.0
+ - nghttp2      1.15.0
  - WinSock      2.2 (on Windows 95+ and Windows CE .NET 4.1+)
 
 ## Build tools