--- a/browser/components/enterprisepolicies/Policies.jsm
+++ b/browser/components/enterprisepolicies/Policies.jsm
@@ -24,16 +24,24 @@ XPCOMUtils.defineLazyGetter(this, "log",
     maxLogLevel: "error",
     maxLogLevelPref: PREF_LOGLEVEL,
   });
 });
 
 this.EXPORTED_SYMBOLS = ["Policies"];
 
 this.Policies = {
+  "BlockAboutAddons": {
+    onBeforeUIStartup(manager, param) {
+      if (param) {
+        manager.disallowFeature("about:addons", true);
+      }
+    }
+  },
+
   "BlockAboutConfig": {
     onBeforeUIStartup(manager, param) {
       if (param) {
         manager.disallowFeature("about:config", true);
       }
     }
   },
 

--- a/browser/components/enterprisepolicies/schemas/policies-schema.json
+++ b/browser/components/enterprisepolicies/schemas/policies-schema.json
@@ -1,12 +1,20 @@
 {
   "$schema": "http://json-schema.org/draft-04/schema#",
   "type": "object",
   "properties": {
+    "BlockAboutAddons": {
+      "description": "Block access to the Add-ons Mananger (about:addons).",
+      "first_available": "60.0",
+
+      "type": "boolean",
+      "enum": [true]
+    },
+
     "BlockAboutConfig": {
       "description": "Blocks access to the about:config page.",
       "first_available": "60.0",
 
       "type": "boolean",
       "enum": [true]
     },
 

--- a/browser/components/enterprisepolicies/tests/browser/browser.ini
+++ b/browser/components/enterprisepolicies/tests/browser/browser.ini
@@ -7,16 +7,17 @@ support-files =
   config_broken_json.json
 
 [browser_policies_broken_json.js]
 [browser_policies_popups_cookies_addons_flash.js]
 [browser_policies_setAndLockPref_API.js]
 [browser_policies_simple_policies.js]
 [browser_policies_validate_and_parse_API.js]
 [browser_policy_app_update.js]
+[browser_policy_block_about_addons.js]
 [browser_policy_block_about_config.js]
 [browser_policy_block_about_profiles.js]
 [browser_policy_block_about_support.js]
 [browser_policy_block_set_desktop_background.js]
 [browser_policy_default_browser_check.js]
 [browser_policy_disable_fxscreenshots.js]
 [browser_policy_display_bookmarks.js]
 [browser_policy_disable_formhistory.js]

new file mode 100644
--- /dev/null
+++ b/browser/components/enterprisepolicies/tests/browser/browser_policy_block_about_addons.js
@@ -0,0 +1,29 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+"use strict";
+
+add_task(async function setup() {
+  await setupPolicyEngineWithJson({
+                                    "policies": {
+                                      "BlockAboutAddons": true
+                                    }
+                                  });
+});
+
+add_task(async function test_about_addons() {
+  let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, "about:addons", false);
+
+  await ContentTask.spawn(tab.linkedBrowser, null, async function() {
+    ok(content.document.documentURI.startsWith("about:neterror"),
+       "about:addons should display the net error page");
+
+    // There is currently a testing-specific race condition that causes this test
+    // to fail, but it is not a problem if we test after the first page load.
+    // Until the race condition is fixed, just make sure to test this *after*
+    // testing the page load.
+    is(Services.policies.isAllowed("about:addons"), false,
+       "Policy Engine should report about:addons as not allowed");
+  });
+
+  await BrowserTestUtils.removeTab(tab);
+});