diff --git a/semantic-release/src/index.ts b/semantic-release/src/index.ts
index a33c7ab..211cd6d 100644
--- a/semantic-release/src/index.ts
+++ b/semantic-release/src/index.ts
@@ -132,11 +132,13 @@ export async function main() {
     );
     if (result) {
       const { lastRelease, nextRelease } = result;
-      setOutput(OUTPUTS.last_release_version, lastRelease.version);
-      setOutput(
-        OUTPUTS.last_release_major_version,
-        semver.major(lastRelease.version),
-      );
+      if (lastRelease.version) {
+        setOutput(OUTPUTS.last_release_version, lastRelease.version);
+        setOutput(
+          OUTPUTS.last_release_major_version,
+          semver.major(lastRelease.version),
+        );
+      }
       if (nextRelease) {
         setOutput(OUTPUTS.new_release_published, "true");
         setOutput(OUTPUTS.new_release_type, nextRelease.type);
diff --git a/semantic-release/test/index.test.ts b/semantic-release/test/index.test.ts
index 408b3e9..f9695ac 100644
--- a/semantic-release/test/index.test.ts
+++ b/semantic-release/test/index.test.ts
@@ -29,9 +29,9 @@ jest.unstable_mockModule("@actions/core", () => ({
   setOutput: setOutputMock,
 }));
 
-const mockRelease = (
-  overrides: Partial<Awaited<ReturnType<typeof semanticRelease>>> = {},
-) => {
+type SemanticRelease = Awaited<ReturnType<typeof semanticRelease>>;
+
+const mockRelease = (overrides: Partial<SemanticRelease> = {}) => {
   const lastRelease = {
     channels: [],
     gitHead: "test",
@@ -147,6 +147,44 @@ describe("semantic-release", () => {
     `);
   });
 
+  test("doesn't set last release outputs if there is no last release", async () => {
+    mockNpmInstall();
+    mockRelease({ lastRelease: false } as unknown as SemanticRelease);
+    await callAction();
+    expect(setOutputMock.mock.calls).toMatchInlineSnapshot(`
+      [
+        [
+          "new-release-published",
+          "true",
+        ],
+        [
+          "new-release-type",
+          "prerelease",
+        ],
+        [
+          "new-release-notes",
+          "New Release notes",
+        ],
+        [
+          "new-release-version",
+          "1.2.3-test",
+        ],
+        [
+          "new-release-major-version",
+          1,
+        ],
+        [
+          "new-release-minor-version",
+          2,
+        ],
+        [
+          "new-release-patch-version",
+          3,
+        ],
+      ]
+    `);
+  });
+
   test("runs semantic release with the extra options", async () => {
     process.env.SEMANTIC_ACTION_BRANCHES = "test";
     process.env.SEMANTIC_ACTION_CI = "true";