diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 97af3b4f..36e9bfb9 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -28,7 +28,7 @@ jobs:
           # Note: Specifying the version of valgrind is not supported.
           # cargo-watch is supported by cargo-binstall (through quickinstall)
           - cargo-hack,cargo-llvm-cov,cargo-minimal-versions,parse-changelog,cargo-udeps,cargo-valgrind,cross,nextest,protoc,shellcheck,shfmt,valgrind,wasm-pack,wasmtime,mdbook,mdbook-linkcheck,cargo-watch
-          - cargo-hack@0.5.21,cargo-llvm-cov@0.5.0,cargo-minimal-versions@0.1.5,parse-changelog@0.5.1,cargo-udeps@0.1.33,cargo-valgrind@2.1.0,cross@0.2.4,nextest@0.9.11,protoc@3.21.6,shellcheck@0.8.0,shfmt@3.5.1,wasm-pack@0.10.3,wasmtime@1.0.0,mdbook@0.4.21,mdbook-linkcheck@0.7.6,cargo-watch@8.1.1
+          - cargo-hack@0.5.21,cargo-llvm-cov@0.5.0,cargo-minimal-versions@0.1.5,parse-changelog@0.5.1,cargo-udeps@0.1.33,cargo-valgrind@2.1.0,cross@0.2.4,nextest@0.9.11,protoc@3.21.7,shellcheck@0.8.0,shfmt@3.5.1,wasm-pack@0.10.3,wasmtime@1.0.0,mdbook@0.4.21,mdbook-linkcheck@0.7.6,cargo-watch@8.1.1
           # Nextest supports basic version ranges as well
           - nextest@0.9
         include:
diff --git a/CHANGELOG.md b/CHANGELOG.md
index a3448a9d..f68bf56d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,8 @@ Note: In this file, do not use the hard wrap in the middle of a sentence for com
 
 ## [Unreleased]
 
+- Update `protoc@latest` to 3.21.7.
+
 ## [1.13.9] - 2022-09-28
 
 - Update `cargo-binstall@latest` to 0.14.0. ([#24](https://github.com/taiki-e/install-action/pull/24), thanks @coltfred)
diff --git a/main.sh b/main.sh
index b81b83b2..c1f69ba0 100755
--- a/main.sh
+++ b/main.sh
@@ -287,7 +287,7 @@ for tool in "${tools[@]}"; do
             ;;
         protoc)
             # https://github.com/protocolbuffers/protobuf/releases
-            latest_version="3.21.6"
+            latest_version="3.21.7"
             repo="protocolbuffers/protobuf"
             case "${version}" in
                 latest) version="${latest_version}" ;;