diff --git a/lib/NetworkManager.js b/lib/NetworkManager.js
index 623d8c8f246..3029286bc86 100644
--- a/lib/NetworkManager.js
+++ b/lib/NetworkManager.js
@@ -86,12 +86,12 @@ class NetworkManager extends EventEmitter {
   _onRequestWillBeSent(event) {
     if (event.redirectResponse) {
       let request = this._idToRequest.get(event.requestId);
-      let response = new Response(request, event.redirectResponse, this._getResponseBody.bind(this, event.requestId));
+      let response = new Response(this._client, request, event.redirectResponse);
       request._response = response;
       this.emit(NetworkManager.Events.Response, response);
       this.emit(NetworkManager.Events.RequestFinished, request);
     }
-    let request = new Request(event.request);
+    let request = new Request(event.requestId, event.request);
     this._idToRequest.set(event.requestId, request);
     this.emit(NetworkManager.Events.Request, request);
   }
@@ -104,7 +104,7 @@ class NetworkManager extends EventEmitter {
     // FileUpload sends a response without a matching request.
     if (!request)
       return;
-    let response = new Response(request, event.response, this._getResponseBody.bind(this, event.requestId));
+    let response = new Response(this._client, request, event.response);
     request._response = response;
     this.emit(NetworkManager.Events.Response, response);
   }
@@ -118,6 +118,7 @@ class NetworkManager extends EventEmitter {
     // @see https://github.com/GoogleChrome/puppeteer/issues/168
     if (!request)
       return;
+    request._completePromiseFulfill.call(null);
     this._idToRequest.delete(event.requestId);
     this.emit(NetworkManager.Events.RequestFinished, request);
   }
@@ -131,26 +132,22 @@ class NetworkManager extends EventEmitter {
     // @see https://github.com/GoogleChrome/puppeteer/issues/168
     if (!request)
       return;
+    request._completePromiseFulfill.call(null);
     this._idToRequest.delete(event.requestId);
     this.emit(NetworkManager.Events.RequestFailed, request);
   }
-
-  /**
-   * @param {string} requestId
-   * @return {!Promise<!Buffer>}
-   */
-  async _getResponseBody(requestId) {
-    let response = await this._client.send('Network.getResponseBody', {requestId});
-    return Buffer.from(response.body, response.base64Encoded ? 'base64' : 'utf8');
-  }
 }
 
 class Request {
   /**
    * @param {!Object} payload
    */
-  constructor(payload) {
+  constructor(requestId, payload) {
+    this._requestId = requestId;
     this._response = null;
+    this._completePromise = new Promise(fulfill => {
+      this._completePromiseFulfill = fulfill;
+    });
     this.url = payload.url;
     this.method = payload.method;
     this.postData = payload.postData;
@@ -168,14 +165,15 @@ helper.tracePublicAPI(Request);
 
 class Response {
   /**
+   * @param {!Connection} client
    * @param {?Request} request
    * @param {!Object} payload
-   * @param {function():!Promise<!Buffer>} contentCallback
    */
-  constructor(request, payload, contentCallback) {
+  constructor(client, request, payload) {
+    this._client = client;
     this._request = request;
-    this._contentCallback = contentCallback;
     this._contentPromise = null;
+
     this.headers = new Map(Object.entries(payload.headers));
     this.ok = payload.status >= 200 && payload.status <= 299;
     this.status = payload.status;
@@ -187,8 +185,14 @@ class Response {
    * @return {!Promise<!Buffer>}
    */
   buffer() {
-    if (!this._contentPromise)
-      this._contentPromise = this._contentCallback();
+    if (!this._contentPromise) {
+      this._contentPromise = this._request._completePromise.then(async() => {
+        let response = await this._client.send('Network.getResponseBody', {
+          requestId: this._request._requestId
+        });
+        return Buffer.from(response.body, response.base64Encoded ? 'base64' : 'utf8');
+      });
+    }
     return this._contentPromise;
   }
 
diff --git a/test/test.js b/test/test.js
index f95bf7de16c..c4b9f11ecf8 100644
--- a/test/test.js
+++ b/test/test.js
@@ -1178,6 +1178,35 @@ describe('Puppeteer', function() {
       expect(await response.text()).toBe('{"foo": "bar"}\n');
       expect(await response.json()).toEqual({foo: 'bar'});
     }));
+    it('Page.Events.Response should not report body unless request is finished', SX(async() => {
+      await page.navigate(EMPTY_PAGE);
+      // Setup server to trap request.
+      let serverResponse = null;
+      server.setRoute('/get', (req, res) => {
+        serverResponse = res;
+        res.write('hello ');
+      });
+      // Setup page to trap response.
+      let pageResponse = null;
+      let requestFinished = false;
+      page.on('response', r => pageResponse = r);
+      page.on('requestfinished', () => requestFinished = true);
+      // send request and wait for server response
+      page.evaluate(() => fetch('./get', { method: 'GET'}));
+      await waitForEvents(page, 'response');
+
+      expect(serverResponse).toBeTruthy();
+      expect(pageResponse).toBeTruthy();
+      expect(pageResponse.status).toBe(200);
+      expect(requestFinished).toBe(false);
+
+      let responseText = pageResponse.text();
+      // Write part of the response and wait for it to be flushed.
+      await new Promise(x => serverResponse.write('wor', x));
+      // Finish response.
+      await new Promise(x => serverResponse.end('ld!', x));
+      expect(await responseText).toBe('hello world!');
+    }));
     it('Page.Events.RequestFailed', SX(async function() {
       page.setRequestInterceptor(request => {
         if (request.url.endsWith('css'))