diff --git a/.github/.cspell/project-dictionary.txt b/.github/.cspell/project-dictionary.txt
index ad5020a64..ecc203437 100644
--- a/.github/.cspell/project-dictionary.txt
+++ b/.github/.cspell/project-dictionary.txt
@@ -2,8 +2,10 @@ almalinux
 archlinux
 bindgen
 binstall
+choco
 coreutils
 cyclonedx
+cygdrive
 deepsource
 distro
 doas
@@ -23,6 +25,7 @@ pwsh
 quickinstall
 rclone
 rdme
+requirechecksums
 sccache
 syft
 udeps
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6a9c17c58..900004028 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -56,6 +56,8 @@ jobs:
           # https://github.com/taiki-e/install-action/pull/518#issuecomment-2160736760
           - os: windows-2022
             bash: msys64
+          - os: windows-2022
+            bash: cygwin
     runs-on: ${{ matrix.os }}
     timeout-minutes: 60
     steps:
@@ -70,6 +72,13 @@ jobs:
           echo "C:\msys64\mingw32\bin" >> $GITHUB_PATH
           echo "C:\msys64\usr\bin" >> $GITHUB_PATH
         if: matrix.bash == 'msys64'
+      - run: |
+          set -eEuxo pipefail
+          choco install --no-progress --requirechecksums cygwin
+          echo "C:\tools\cygwin\bin" >> $GITHUB_PATH
+          echo "C:\tools\cygwin\usr\bin" >> $GITHUB_PATH
+        if: matrix.bash == 'cygwin'
+      - run: env
       - uses: ./
         with:
           tool: ${{ steps.tool-list.outputs.tool }}
@@ -100,6 +109,7 @@ jobs:
           if [[ "$(cargo binstall -V)" != "$(jq -r '.latest.version' manifests/cargo-binstall.json)" ]]; then
             exit 1
           fi
+        if: matrix.bash != 'cygwin'
 
   test-container:
     strategy:
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4d823c3ef..cdbe031d2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,9 +10,16 @@ Note: In this file, do not use the hard wrap in the middle of a sentence for com
 
 ## [Unreleased]
 
+- Workaround Cygwin bash's buggy behavior. ([#534](https://github.com/taiki-e/install-action/pull/534))
+  This fixes an installation issue when default bash was overridden like the following:
+
+  ```sh
+  echo "C:\tools\cygwin\bin" >> $GITHUB_PATH
+  ```
+
 ## [2.38.3] - 2024-06-11
 
-- Workaround msys64 bash's buggy behavior. ([#533](https://github.com/taiki-e/install-action/pull/533))
+- Workaround MSYS64 bash's buggy behavior. ([#533](https://github.com/taiki-e/install-action/pull/533))
   This fixes an installation issue when default bash was overridden like the following:
 
   ```sh
diff --git a/main.sh b/main.sh
index fddf858e7..b7b84c108 100755
--- a/main.sh
+++ b/main.sh
@@ -400,7 +400,7 @@ init_install_action_bin_dir() {
 }
 canonicalize_windows_path() {
     case "${host_os}" in
-        windows) sed <<<"$1" 's/^\/c\//C:\\/; s/\//\\/g' ;;
+        windows) sed <<<"$1" 's/^\/cygdrive\//\//; s/^\/c\//C:\\/; s/\//\\/g' ;;
         *) echo "$1" ;;
     esac
 }
@@ -521,8 +521,10 @@ if [[ "${host_os}" == "windows" ]]; then
         if [[ -d "${home/\/home\//\/c\/Users\/}" ]]; then
             # MSYS2 https://github.com/taiki-e/install-action/pull/518#issuecomment-2160736760
             home="${home/\/home\//\/c\/Users\/}"
+        elif [[ -d "${home/\/home\//\/cygdrive\/c\/Users\/}" ]]; then
+            # Cygwin https://github.com/taiki-e/install-action/issues/224#issuecomment-1720196288
+            home="${home/\/home\//\/cygdrive\/c\/Users\/}"
         else
-            # TODO: Cygwin https://github.com/taiki-e/install-action/issues/224#issuecomment-1720196288
             warn "\$HOME starting /home/ (${home}) on Windows bash is usually fake path, this may cause installation issue"
         fi
     fi