diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 6fe85fc5..f0fd6dce 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -116,7 +116,7 @@ jobs:
     - name: Build nghttp3
       if: matrix.http3 == 'http3'
       run: |
-        git clone --depth 1 -b v0.4.0 https://github.com/ngtcp2/nghttp3
+        git clone --depth 1 -b v0.4.1 https://github.com/ngtcp2/nghttp3
         cd nghttp3
         autoreconf -i
         ./configure --prefix=$PWD/build --enable-lib-only
@@ -125,7 +125,7 @@ jobs:
     - name: Build ngtcp2
       if: matrix.http3 == 'http3'
       run: |
-        git clone --depth 1 -b v0.4.0 https://github.com/ngtcp2/ngtcp2
+        git clone --depth 1 -b v0.5.0 https://github.com/ngtcp2/ngtcp2
         cd ngtcp2
         autoreconf -i
         ./configure --prefix=$PWD/build --enable-lib-only PKG_CONFIG_PATH="../openssl/build/lib/pkgconfig"
diff --git a/README.rst b/README.rst
index 70bbf220..ece02ebb 100644
--- a/README.rst
+++ b/README.rst
@@ -154,7 +154,7 @@ following libraries are required:
   <https://github.com/quictls/openssl/tree/OpenSSL_1_1_1o+quic>`_; or
   `BoringSSL <https://boringssl.googlesource.com/boringssl/>`_ (commit
   36a41bf0bf2dd3176f8780e09c03585351f29963)
-* `ngtcp2 <https://github.com/ngtcp2/ngtcp2>`_ >= 0.4.0
+* `ngtcp2 <https://github.com/ngtcp2/ngtcp2>`_ >= 0.5.0
 * `nghttp3 <https://github.com/ngtcp2/nghttp3>`_ >= 0.4.0
 
 Use ``--enable-http3`` configure option to enable HTTP/3 feature for
@@ -366,7 +366,7 @@ Build nghttp3:
 
 .. code-block:: text
 
-   $ git clone --depth 1 -b v0.4.0 https://github.com/ngtcp2/nghttp3
+   $ git clone --depth 1 -b v0.4.1 https://github.com/ngtcp2/nghttp3
    $ cd nghttp3
    $ autoreconf -i
    $ ./configure --prefix=$PWD/build --enable-lib-only
@@ -378,7 +378,7 @@ Build ngtcp2:
 
 .. code-block:: text
 
-   $ git clone --depth 1 -b v0.4.0 https://github.com/ngtcp2/ngtcp2
+   $ git clone --depth 1 -b v0.5.0 https://github.com/ngtcp2/ngtcp2
    $ cd ngtcp2
    $ autoreconf -i
    $ ./configure --prefix=$PWD/build --enable-lib-only \
diff --git a/configure.ac b/configure.ac
index 45eedbaf..f6c935d8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -540,7 +540,7 @@ fi
 # ngtcp2 (for src)
 have_libngtcp2=no
 if test "x${request_libngtcp2}" != "xno"; then
-  PKG_CHECK_MODULES([LIBNGTCP2], [libngtcp2 >= 0.4.0], [have_libngtcp2=yes],
+  PKG_CHECK_MODULES([LIBNGTCP2], [libngtcp2 >= 0.5.0], [have_libngtcp2=yes],
                     [have_libngtcp2=no])
   if test "x${have_libngtcp2}" = "xno"; then
     AC_MSG_NOTICE($LIBNGTCP2_PKG_ERRORS)
@@ -557,7 +557,7 @@ have_libngtcp2_crypto_openssl=no
 if test "x${have_ssl_is_quic}" = "xyes" &&
    test "x${request_libngtcp2}" != "xno"; then
   PKG_CHECK_MODULES([LIBNGTCP2_CRYPTO_OPENSSL],
-                    [libngtcp2_crypto_openssl >= 0.4.0],
+                    [libngtcp2_crypto_openssl >= 0.5.0],
                     [have_libngtcp2_crypto_openssl=yes],
                     [have_libngtcp2_crypto_openssl=no])
   if test "x${have_libngtcp2_crypto_openssl}" = "xno"; then
diff --git a/docker/Dockerfile b/docker/Dockerfile
index 14762ae8..ab676cc9 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -15,7 +15,7 @@ RUN git clone --depth 1 -b OpenSSL_1_1_1o+quic https://github.com/quictls/openss
     cd .. && \
     rm -rf openssl
 
-RUN git clone --depth 1 -b v0.4.0 https://github.com/ngtcp2/nghttp3 && \
+RUN git clone --depth 1 -b v0.4.1 https://github.com/ngtcp2/nghttp3 && \
     cd nghttp3 && \
     autoreconf -i && \
     ./configure --enable-lib-only && \
@@ -24,7 +24,7 @@ RUN git clone --depth 1 -b v0.4.0 https://github.com/ngtcp2/nghttp3 && \
     cd .. && \
     rm -rf nghttp3
 
-RUN git clone --depth 1 -b v0.4.0 https://github.com/ngtcp2/ngtcp2 && \
+RUN git clone --depth 1 -b v0.5.0 https://github.com/ngtcp2/ngtcp2 && \
     cd ngtcp2 && \
     autoreconf -i && \
     ./configure --enable-lib-only \