diff --git a/bundler.js b/bundler.js
index 81c64bac6..d0f40eca3 100644
--- a/bundler.js
+++ b/bundler.js
@@ -236,7 +236,8 @@ async function computeBaseKey(platform, engine, version, lockFile, cacheVersion)
   const cwd = process.cwd()
   const bundleWith = process.env['BUNDLE_WITH'] || ''
   const bundleWithout = process.env['BUNDLE_WITHOUT'] || ''
-  let key = `setup-ruby-bundler-cache-v6-${common.getOSNameVersionArch()}-${engine}-${version}-wd-${cwd}-with-${bundleWith}-without-${bundleWithout}`
+  const bundleOnly = process.env['BUNDLE_ONLY'] || ''
+  let key = `setup-ruby-bundler-cache-v6-${common.getOSNameVersionArch()}-${engine}-${version}-wd-${cwd}-with-${bundleWith}-without-${bundleWithout}-only-${bundleOnly}`
 
   if (cacheVersion !== DEFAULT_CACHE_VERSION) {
     key += `-v-${cacheVersion}`
diff --git a/dist/index.js b/dist/index.js
index 9e81ee702..728353204 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -250,7 +250,8 @@ async function computeBaseKey(platform, engine, version, lockFile, cacheVersion)
   const cwd = process.cwd()
   const bundleWith = process.env['BUNDLE_WITH'] || ''
   const bundleWithout = process.env['BUNDLE_WITHOUT'] || ''
-  let key = `setup-ruby-bundler-cache-v6-${common.getOSNameVersionArch()}-${engine}-${version}-wd-${cwd}-with-${bundleWith}-without-${bundleWithout}`
+  const bundleOnly = process.env['BUNDLE_ONLY'] || ''
+  let key = `setup-ruby-bundler-cache-v6-${common.getOSNameVersionArch()}-${engine}-${version}-wd-${cwd}-with-${bundleWith}-without-${bundleWithout}-only-${bundleOnly}`
 
   if (cacheVersion !== DEFAULT_CACHE_VERSION) {
     key += `-v-${cacheVersion}`