diff --git a/__tests__/setup-go.test.ts b/__tests__/setup-go.test.ts
index 70f2166eb..182e7bda7 100644
--- a/__tests__/setup-go.test.ts
+++ b/__tests__/setup-go.test.ts
@@ -904,6 +904,29 @@ use .
       );
     });
 
+    it('go-version accepts a go.mod file', async () => {
+      inputs['go-version'] = 'go.mod';
+      existsSpy.mockImplementation(() => true);
+      readFileSpy.mockImplementation(() => Buffer.from(goModContents));
+
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith('Setup go version spec 1.14');
+      expect(logSpy).toHaveBeenCalledWith('Attempting to download 1.14...');
+      expect(logSpy).toHaveBeenCalledWith('matching 1.14...');
+    });
+
+    it('go-version reports a read failure', async () => {
+      inputs['go-version'] = 'path/to/go.mod';
+      existsSpy.mockImplementation(() => false);
+
+      await main.run();
+
+      expect(cnSpy).toHaveBeenCalledWith(
+        `::error::The specified go version file at: path/to/go.mod does not exist${osm.EOL}`
+      );
+    });
+
     it('acquires specified architecture of go', async () => {
       for (const {arch, version, osSpec} of [
         {arch: 'amd64', version: '1.13.7', osSpec: 'linux'},
diff --git a/dist/setup/index.js b/dist/setup/index.js
index 9ad3784ea..e3b4d9152 100644
--- a/dist/setup/index.js
+++ b/dist/setup/index.js
@@ -88749,12 +88749,15 @@ function parseGoVersion(versionString) {
 exports.parseGoVersion = parseGoVersion;
 function resolveVersionInput() {
     let version = core.getInput('go-version');
-    const versionFilePath = core.getInput('go-version-file');
+    let versionFilePath = core.getInput('go-version-file');
     if (version && versionFilePath) {
         core.warning('Both go-version and go-version-file inputs are specified, only go-version will be used');
     }
     if (version) {
-        return version;
+        if (!version.endsWith('go.mod')) {
+            return version;
+        }
+        versionFilePath = version;
     }
     if (versionFilePath) {
         if (!fs_1.default.existsSync(versionFilePath)) {
diff --git a/src/main.ts b/src/main.ts
index 690d277f9..2fdeb8ae0 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -137,7 +137,7 @@ export function parseGoVersion(versionString: string): string {
 
 function resolveVersionInput(): string {
   let version = core.getInput('go-version');
-  const versionFilePath = core.getInput('go-version-file');
+  let versionFilePath = core.getInput('go-version-file');
 
   if (version && versionFilePath) {
     core.warning(
@@ -146,7 +146,10 @@ function resolveVersionInput(): string {
   }
 
   if (version) {
-    return version;
+    if (!version.endsWith('go.mod')) {
+      return version;
+    }
+    versionFilePath = version;
   }
 
   if (versionFilePath) {