diff --git a/dist/index.js b/dist/index.js
index 5f991cf..a5780c1 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -43,6 +43,7 @@ function run() {
         try {
             const githubToken = core.getInput('github_token', { required: true });
             const body = core.getInput('body', { required: true });
+            const deduplicate = core.getInput('deduplicate', { required: false });
             const octokit = github.getOctokit(githubToken);
             let { owner, repo } = github.context.repo;
             if (core.getInput('repo')) {
@@ -51,6 +52,22 @@ function run() {
             const number = core.getInput('number') === ''
                 ? github.context.issue.number
                 : parseInt(core.getInput('number'));
+            if (deduplicate) {
+                const comments = yield octokit.issues.listComments({
+                    owner,
+                    repo,
+                    issue_number: number
+                });
+                const comment_ids = comments.data.filter(comment => comment.body.includes(deduplicate)).map(comment => comment.id);
+                for (const comment_id of comment_ids) {
+                    yield octokit.issues.deleteComment({
+                        owner,
+                        repo,
+                        issue_number: number,
+                        comment_id
+                    });
+                }
+            }
             yield octokit.issues.createComment({
                 owner,
                 repo,
diff --git a/src/main.ts b/src/main.ts
index c08c019..017a97a 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -5,6 +5,7 @@ async function run(): Promise<void> {
   try {
     const githubToken = core.getInput('github_token', { required: true });
     const body = core.getInput('body', { required: true });
+    const deduplicate = core.getInput('deduplicate', { required: false });
 
     const octokit = github.getOctokit(githubToken);
 
@@ -18,6 +19,25 @@ async function run(): Promise<void> {
         ? github.context.issue.number
         : parseInt(core.getInput('number'));
 
+    if (deduplicate) {
+      const comments = await octokit.issues.listComments({
+        owner,
+        repo,
+        issue_number: number
+      });
+      const comment_ids = comments.data.filter(comment =>
+        comment.body.includes(deduplicate)
+      ).map(comment => comment.id);
+      for (const comment_id of comment_ids) {
+        await octokit.issues.deleteComment({
+          owner,
+          repo,
+          issue_number: number,
+          comment_id
+        });
+      }
+    }
+
     await octokit.issues.createComment({
       owner,
       repo,