diff --git a/lib/github-comment.js b/lib/github-comment.js
index 221bc195..53075604 100644
--- a/lib/github-comment.js
+++ b/lib/github-comment.js
@@ -14,3 +14,16 @@ exports.createPrComment = function createPrComment ({ owner, repo, number, logge
     }
   })
 }
+
+exports.editPrComment = function createPrComment ({ owner, repo, logger }, commentId, body) {
+  githubClient.issues.editComment({
+    owner,
+    repo,
+    id: commentId,
+    body
+  }, (err) => {
+    if (err) {
+      logger.error(err, 'Error while editing comment on GitHub')
+    }
+  })
+}
diff --git a/lib/push-jenkins-update.js b/lib/push-jenkins-update.js
index 25bd1965..0c7fe822 100644
--- a/lib/push-jenkins-update.js
+++ b/lib/push-jenkins-update.js
@@ -3,7 +3,8 @@
 const url = require('url')
 
 const githubClient = require('./github-client')
-const { createPrComment } = require('./github-comment')
+const { createPrComment, editPrComment } = require('./github-comment')
+const botUsername = require('./bot-username')
 
 function pushStarted (options, build, cb) {
   const pr = findPrInRef(build.ref)
@@ -15,7 +16,19 @@ function pushStarted (options, build, cb) {
   const optsWithPr = Object.assign({ pr }, options)
 
   if (build.identifier === 'node-test-pull-request' && build.status === 'pending') {
-    createPrComment(Object.assign({ number: pr }, options), `CI: ${build.url}`)
+    findExistingCiComment(optsWithPr, logger, (err, existingComment) => {
+      if (err) {
+        logger.error(err, 'Got error while retrieving GitHub comments for PR')
+        return
+      }
+
+      const body = `CI: ${build.url}`
+      if (existingComment === undefined) {
+        createPrComment(Object.assign({ number: pr }, options), body)
+      } else {
+        editPrComment(options, existingComment.id, `${existingComment.body}\n${body}`)
+      }
+    })
   }
 
   findLatestCommitInPr(optsWithPr, (err, latestCommit) => {
@@ -118,6 +131,21 @@ function createGhStatus (options, logger, cb) {
   })
 }
 
+function findExistingCiComment (options, logger, cb) {
+  githubClient.issues.getComments({
+    owner: options.owner,
+    repo: options.repo,
+    number: options.pr
+  }, (err, response) => {
+    if (err) {
+      return cb(err)
+    }
+
+    const comments = response.data.reverse()
+    cb(null, comments.find((comment) => comment.body.startsWith('CI: ') && comment.user.login === botUsername))
+  })
+}
+
 function validate (payload) {
   const isString = (param) => typeof (payload[param]) === 'string'
   return ['identifier', 'status', 'message', 'commit', 'url'].every(isString)
diff --git a/test/_fixtures/authenticated-user.json b/test/_fixtures/authenticated-user.json
new file mode 100644
index 00000000..b9aeb143
--- /dev/null
+++ b/test/_fixtures/authenticated-user.json
@@ -0,0 +1,33 @@
+{
+  "login": "nodejs-github-bot",
+  "id": 18269663,
+  "node_id": "MDQ6VXNlcjE4MjY5NjYz",
+  "avatar_url": "https://avatars1.githubusercontent.com/u/18269663?v=4",
+  "gravatar_id": "",
+  "url": "https://api.github.com/users/nodejs-github-bot",
+  "html_url": "https://github.com/nodejs-github-bot",
+  "followers_url": "https://api.github.com/users/nodejs-github-bot/followers",
+  "following_url": "https://api.github.com/users/nodejs-github-bot/following{/other_user}",
+  "gists_url": "https://api.github.com/users/nodejs-github-bot/gists{/gist_id}",
+  "starred_url": "https://api.github.com/users/nodejs-github-bot/starred{/owner}{/repo}",
+  "subscriptions_url": "https://api.github.com/users/nodejs-github-bot/subscriptions",
+  "organizations_url": "https://api.github.com/users/nodejs-github-bot/orgs",
+  "repos_url": "https://api.github.com/users/nodejs-github-bot/repos",
+  "events_url": "https://api.github.com/users/nodejs-github-bot/events{/privacy}",
+  "received_events_url": "https://api.github.com/users/nodejs-github-bot/received_events",
+  "type": "User",
+  "site_admin": false,
+  "name": "Node.js GitHub Bot",
+  "company": null,
+  "blog": "https://github.com/nodejs/github-bot",
+  "location": null,
+  "email": null,
+  "hireable": null,
+  "bio": null,
+  "public_repos": 1,
+  "public_gists": 0,
+  "followers": 21,
+  "following": 0,
+  "created_at": "2016-04-04T18:31:48Z",
+  "updated_at": "2018-11-21T02:22:03Z"
+}
diff --git a/test/_fixtures/pull-request-comments-with-ci-comment.json b/test/_fixtures/pull-request-comments-with-ci-comment.json
new file mode 100644
index 00000000..226fc143
--- /dev/null
+++ b/test/_fixtures/pull-request-comments-with-ci-comment.json
@@ -0,0 +1,126 @@
+[
+  {
+    "url": "https://api.github.com/repos/nodejs/node/issues/comments/475182143",
+    "html_url": "https://github.com/nodejs/node/pull/26837#issuecomment-475182143",
+    "issue_url": "https://api.github.com/repos/nodejs/node/issues/26837",
+    "id": 475182143,
+    "node_id": "MDEyOklzc3VlQ29tbWVudDQ3NTE4MjE0Mw==",
+    "user": {
+      "login": "nodejs-github-bot",
+      "id": 18269663,
+      "node_id": "MDQ6VXNlcjE4MjY5NjYz",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/18269663?v=4",
+      "gravatar_id": "",
+      "url": "https://api.github.com/users/nodejs-github-bot",
+      "html_url": "https://github.com/nodejs-github-bot",
+      "followers_url": "https://api.github.com/users/nodejs-github-bot/followers",
+      "following_url": "https://api.github.com/users/nodejs-github-bot/following{/other_user}",
+      "gists_url": "https://api.github.com/users/nodejs-github-bot/gists{/gist_id}",
+      "starred_url": "https://api.github.com/users/nodejs-github-bot/starred{/owner}{/repo}",
+      "subscriptions_url": "https://api.github.com/users/nodejs-github-bot/subscriptions",
+      "organizations_url": "https://api.github.com/users/nodejs-github-bot/orgs",
+      "repos_url": "https://api.github.com/users/nodejs-github-bot/repos",
+      "events_url": "https://api.github.com/users/nodejs-github-bot/events{/privacy}",
+      "received_events_url": "https://api.github.com/users/nodejs-github-bot/received_events",
+      "type": "User",
+      "site_admin": false
+    },
+    "created_at": "2019-03-21T10:42:26Z",
+    "updated_at": "2019-03-21T10:42:26Z",
+    "author_association": "MEMBER",
+    "body": "@addaleax build started: https://ci.nodejs.org/blue/organizations/jenkins/node-test-pull-request-lite-pipeline/detail/node-test-pull-request-lite-pipeline/2998/pipeline"
+  },
+  {
+    "url": "https://api.github.com/repos/nodejs/node/issues/comments/475368357",
+    "html_url": "https://github.com/nodejs/node/pull/26837#issuecomment-475368357",
+    "issue_url": "https://api.github.com/repos/nodejs/node/issues/26837",
+    "id": 475368357,
+    "node_id": "MDEyOklzc3VlQ29tbWVudDQ3NTM2ODM1Nw==",
+    "user": {
+      "login": "addaleax",
+      "id": 899444,
+      "node_id": "MDQ6VXNlcjg5OTQ0NA==",
+      "avatar_url": "https://avatars2.githubusercontent.com/u/899444?v=4",
+      "gravatar_id": "",
+      "url": "https://api.github.com/users/addaleax",
+      "html_url": "https://github.com/addaleax",
+      "followers_url": "https://api.github.com/users/addaleax/followers",
+      "following_url": "https://api.github.com/users/addaleax/following{/other_user}",
+      "gists_url": "https://api.github.com/users/addaleax/gists{/gist_id}",
+      "starred_url": "https://api.github.com/users/addaleax/starred{/owner}{/repo}",
+      "subscriptions_url": "https://api.github.com/users/addaleax/subscriptions",
+      "organizations_url": "https://api.github.com/users/addaleax/orgs",
+      "repos_url": "https://api.github.com/users/addaleax/repos",
+      "events_url": "https://api.github.com/users/addaleax/events{/privacy}",
+      "received_events_url": "https://api.github.com/users/addaleax/received_events",
+      "type": "User",
+      "site_admin": false
+    },
+    "created_at": "2019-03-21T19:20:30Z",
+    "updated_at": "2019-03-21T19:20:30Z",
+    "author_association": "MEMBER",
+    "body": "CI: https://ci.nodejs.org/job/node-test-pull-request/21737/"
+  },
+  {
+    "url": "https://api.github.com/repos/nodejs/node/issues/comments/475385809",
+    "html_url": "https://github.com/nodejs/node/pull/26837#issuecomment-475385809",
+    "issue_url": "https://api.github.com/repos/nodejs/node/issues/26837",
+    "id": 475385809,
+    "node_id": "MDEyOklzc3VlQ29tbWVudDQ3NTM4NTgwOQ==",
+    "user": {
+      "login": "addaleax",
+      "id": 899444,
+      "node_id": "MDQ6VXNlcjg5OTQ0NA==",
+      "avatar_url": "https://avatars2.githubusercontent.com/u/899444?v=4",
+      "gravatar_id": "",
+      "url": "https://api.github.com/users/addaleax",
+      "html_url": "https://github.com/addaleax",
+      "followers_url": "https://api.github.com/users/addaleax/followers",
+      "following_url": "https://api.github.com/users/addaleax/following{/other_user}",
+      "gists_url": "https://api.github.com/users/addaleax/gists{/gist_id}",
+      "starred_url": "https://api.github.com/users/addaleax/starred{/owner}{/repo}",
+      "subscriptions_url": "https://api.github.com/users/addaleax/subscriptions",
+      "organizations_url": "https://api.github.com/users/addaleax/orgs",
+      "repos_url": "https://api.github.com/users/addaleax/repos",
+      "events_url": "https://api.github.com/users/addaleax/events{/privacy}",
+      "received_events_url": "https://api.github.com/users/addaleax/received_events",
+      "type": "User",
+      "site_admin": false
+    },
+    "created_at": "2019-03-21T20:16:21Z",
+    "updated_at": "2019-03-21T20:16:21Z",
+    "author_association": "MEMBER",
+    "body": "Resume CI: https://ci.nodejs.org/job/node-test-pull-request/21739/"
+  },
+  {
+    "url": "https://api.github.com/repos/nodejs/node/issues/comments/476584580",
+    "html_url": "https://github.com/nodejs/node/pull/26837#issuecomment-476584580",
+    "issue_url": "https://api.github.com/repos/nodejs/node/issues/26837",
+    "id": 476584580,
+    "node_id": "MDEyOklzc3VlQ29tbWVudDQ3NjU4NDU4MA==",
+    "user": {
+      "login": "nodejs-github-bot",
+      "id": 18269663,
+      "node_id": "MDQ6VXNlcjE4MjY5NjYz",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/18269663?v=4",
+      "gravatar_id": "",
+      "url": "https://api.github.com/users/nodejs-github-bot",
+      "html_url": "https://github.com/nodejs-github-bot",
+      "followers_url": "https://api.github.com/users/nodejs-github-bot/followers",
+      "following_url": "https://api.github.com/users/nodejs-github-bot/following{/other_user}",
+      "gists_url": "https://api.github.com/users/nodejs-github-bot/gists{/gist_id}",
+      "starred_url": "https://api.github.com/users/nodejs-github-bot/starred{/owner}{/repo}",
+      "subscriptions_url": "https://api.github.com/users/nodejs-github-bot/subscriptions",
+      "organizations_url": "https://api.github.com/users/nodejs-github-bot/orgs",
+      "repos_url": "https://api.github.com/users/nodejs-github-bot/repos",
+      "events_url": "https://api.github.com/users/nodejs-github-bot/events{/privacy}",
+      "received_events_url": "https://api.github.com/users/nodejs-github-bot/received_events",
+      "type": "User",
+      "site_admin": false
+    },
+    "created_at": "2019-03-26T11:25:56Z",
+    "updated_at": "2019-03-26T11:25:56Z",
+    "author_association": "MEMBER",
+    "body": "CI: https://ci.nodejs.org/job/node-test-pull-request/21904/"
+  }
+]
diff --git a/test/integration/push-jenkins-update.test.js b/test/integration/push-jenkins-update.test.js
index 7184d81a..7a77a5f2 100644
--- a/test/integration/push-jenkins-update.test.js
+++ b/test/integration/push-jenkins-update.test.js
@@ -104,12 +104,18 @@ tap.test('Forwards payload provided in incoming POST to GitHub status API', (t)
 
 tap.test('Posts a CI comment in the related PR when Jenkins build is named node-test-pull-request', (t) => {
   const fixture = readFixture('jenkins-test-pull-request-success-payload.json')
-  const commentScope = nock('https://api.github.com')
+  const createCommentScope = nock('https://api.github.com')
                         .filteringPath(ignoreQueryParams)
                         .post('/repos/nodejs/node/issues/12345/comments', { body: 'CI: https://ci.nodejs.org/job/node-test-pull-request/21633/' })
                         .reply(200)
 
+  nock('https://api.github.com')
+    .filteringPath(ignoreQueryParams)
+    .get('/repos/nodejs/node/issues/12345/comments')
+    .reply(200, [])
+
   // we don't care about asserting the scopes below, just want to stop the requests from actually being sent
+  setupGetBotUsernameMock()
   setupGetCommitsMock('node')
   nock('https://api.github.com')
     .filteringPath(ignoreQueryParams)
@@ -123,7 +129,43 @@ tap.test('Posts a CI comment in the related PR when Jenkins build is named node-
     .send(fixture)
     .expect(201)
     .end((err, res) => {
-      commentScope.done()
+      createCommentScope.done()
+      t.equal(err, null)
+    })
+})
+
+tap.test('Edits existing CI comment when bot has posted a CI comment before', (t) => {
+  const incomingReqFixture = readFixture('jenkins-test-pull-request-success-payload.json')
+  const existingCommentsFixture = readFixture('pull-request-comments-with-ci-comment.json')
+
+  const editCommentScope = nock('https://api.github.com')
+                        .filteringPath(ignoreQueryParams)
+                        .patch('/repos/nodejs/node/issues/comments/476584580', {
+                          body: `CI: https://ci.nodejs.org/job/node-test-pull-request/21904/\nCI: https://ci.nodejs.org/job/node-test-pull-request/21633/`
+                        })
+                        .reply(200)
+
+  nock('https://api.github.com')
+    .filteringPath(ignoreQueryParams)
+    .get('/repos/nodejs/node/issues/12345/comments')
+    .reply(200, existingCommentsFixture)
+
+  // we don't care about asserting the scopes below, just want to stop the requests from actually being sent
+  setupGetBotUsernameMock()
+  setupGetCommitsMock('node')
+  nock('https://api.github.com')
+    .filteringPath(ignoreQueryParams)
+    .post('/repos/nodejs/node/statuses/8a5fec2a6bade91e544a30314d7cf21f8a200de1')
+    .reply(201)
+
+  t.plan(1)
+
+  supertest(app)
+    .post('/node/jenkins/start')
+    .send(incomingReqFixture)
+    .expect(201)
+    .end((err, res) => {
+      editCommentScope.done()
       t.equal(err, null)
     })
 })
@@ -205,6 +247,13 @@ function setupGetCommitsMock (repoName) {
             .reply(200, commitsResponse)
 }
 
+function setupGetBotUsernameMock () {
+  nock('https://api.github.com')
+    .filteringPath(ignoreQueryParams)
+    .get('/user')
+    .reply(200, readFixture('authenticated-user.json'))
+}
+
 function ignoreQueryParams (pathAndQuery) {
   return url.parse(pathAndQuery, true).pathname
 }