diff --git a/third_party/polymer/README.chromium b/third_party/polymer/README.chromium
index afbdc267067158..bc16ae73561be3 100644
--- a/third_party/polymer/README.chromium
+++ b/third_party/polymer/README.chromium
@@ -1,8 +1,8 @@
 Name: Polymer
 Short Name: polymer
-URL: http://www.polymer-project.org
-Version: 1.9.1
-Revision: (see v1_0/components_summary.txt)
+URL: https://polymer-library.polymer-project.org
+Version: 3.2.0
+Revision: N/A
 License: BSD
 License File: LICENSE.polymer
 Security Critical: no
@@ -10,7 +10,7 @@ Security Critical: no
 Description:
 This directory contains a copy of the Polymer framework and some elements from
 the Polymer elements catalog (https://elements.polymer-project.org/). See
-v1_0/components_summary.txt for a full list of components.
+v3_0/package.json for a full list of components.
 
 The source git repositories can be found at:
 https://github.com/Polymer/polymer
@@ -26,7 +26,7 @@ becomes smaller and better over time.
 technologies called the Polymer.
 
 Local Modifications:
-- Applied modifications that can be found in v1_0/chromium.patch.
+- Applied modifications that can be found in v3_0/chromium.patch.
 - All inline JavaScript blocks are extracted from Polymer HTML elements to
 external JS files. This version of the Polymer is used in a web UI, where CSP
 forbids an execution of inline scripts. The extraction was made with the help of
@@ -34,29 +34,17 @@ the Crisper tool (https://github.com/PolymerLabs/crisper).
 - Removed executable bit from some files.
 - Resolved encoding issues.
 - Replaced CRLF line endings with LF line endings in text files.
-- Removed files that are not needed by Chromium, see v1_0/rsync_exclude.txt.
+- Removed files that are not needed by Chromium, see v3_0/rsync_exclude.txt.
 - Re-implemented <paper-ripple> using Web Animations API (which, as of
   2/21/2017 does not work in Safari or IE). This is a complete fork from
   Polymer's <paper-ripple>.
 - Removed CSS properties that are not needed in Chromium using
   css_strip_prefixes.py script.
-- Bundled and minified Polymer 2 with minify_polymer.py, since Polymer 2 repo
-  does not distribute minified files (unlike Polymer 1).
-- Note that the Polymer 2 bundle does not include dir-mixin.html which is
+- Bundled and minified Polymer 3 with minify_polymer.py, since Polymer 3 repo
+  does not distribute minified files.
+- Note that the Polymer 3 bundle does not include dir-mixin.js which is
   responsible for polyfylling :dir() CSS rules, because it causes a performance
   regression (and it is unnecessary), see crbug.com/899603 for more context.
 
 To restore a content of the 'components-chromium' directory from scratch, run
-./v1_0/reproduce.sh on a Linux machine.
-
-Note on Bower:
-The directory can be updated by running "bower update". A new component can be
-installed by running "bower install -S PolymerElements/<component>#version".
-Be sure to add the .bower.json file to the repository as it includes the
-revision information of the polymer component.
-Also be sure that you listed all the added packages in bower.json.
-
-Polymer 3 notes
-Polymer 3 resides under v3_0/, and uses NPM instead of Bower. To restore the
-contents of the 'components-chromium' directory from scratch, run
 ./v3_0/reproduce.sh on a Linux machine.
diff --git a/third_party/polymer/v1_0/css_strip_prefixes.py b/third_party/polymer/v3_0/css_strip_prefixes.py
similarity index 100%
rename from third_party/polymer/v1_0/css_strip_prefixes.py
rename to third_party/polymer/v3_0/css_strip_prefixes.py
diff --git a/third_party/polymer/v1_0/css_strip_prefixes_test.py b/third_party/polymer/v3_0/css_strip_prefixes_test.py
similarity index 100%
rename from third_party/polymer/v1_0/css_strip_prefixes_test.py
rename to third_party/polymer/v3_0/css_strip_prefixes_test.py
diff --git a/third_party/polymer/v1_0/generate_gn.sh b/third_party/polymer/v3_0/generate_gn.sh
similarity index 60%
rename from third_party/polymer/v1_0/generate_gn.sh
rename to third_party/polymer/v3_0/generate_gn.sh
index 2cae8c9a977517..60eb8a7765232e 100755
--- a/third_party/polymer/v1_0/generate_gn.sh
+++ b/third_party/polymer/v3_0/generate_gn.sh
@@ -6,26 +6,13 @@
 dirs=$(find components-chromium -type d | grep -v 'components-chromium/polymer')
 
 gn_files=''
-polymer_version=$1
-
-if [ "$polymer_version" -eq 3 ];
-  then
-    file_extension="js";
-  else
-    file_extension="html";
-fi
 
 for dir in $dirs; do
-  files=$(\ls $dir/*.$file_extension 2>/dev/null)
+  files=$(\ls $dir/*.js 2>/dev/null)
   if [ "$files" ]; then
     echo "Analyzing $dir"
     gn_file="$dir/BUILD.gn"
-    if [ "$polymer_version" -eq 3 ];
-      then
-        content=$(../../../tools/polymer/generate_gn_v3.py $files);
-      else
-        content=$(../../../tools/polymer/generate_gn.py $files);
-    fi
+    content=$(../../../tools/polymer/generate_gn_v3.py $files);
     if [ "$content" ]; then
       echo "Writing $gn_file"
       echo "$content" > "$gn_file"
@@ -40,10 +27,6 @@ done
 
 # Copy components-chromium/polymer BUILD.gn file manually, since it is not
 # auto-generated by generate_gn_v3.py.
-if [ "$polymer_version" -eq 3 ];
-  then
-    cp ./BUILD_polymer.gn "components-chromium/polymer/BUILD.gn"
-fi
-
+cp ./BUILD_polymer.gn "components-chromium/polymer/BUILD.gn"
 
 git cl format $gn_files
diff --git a/third_party/polymer/v3_0/reproduce.sh b/third_party/polymer/v3_0/reproduce.sh
index a9af73b0950da6..25b1481eebe71b 100755
--- a/third_party/polymer/v3_0/reproduce.sh
+++ b/third_party/polymer/v3_0/reproduce.sh
@@ -108,13 +108,13 @@ if [[ ! -z "${new}${deleted}" ]]; then
 fi
 
 echo 'Stripping unnecessary prefixed CSS rules...'
-python ../v1_0/css_strip_prefixes.py --file_extension=js
+python css_strip_prefixes.py --file_extension=js
 
 echo 'Generating -rgb versions of --google-* vars in paper-style/colors.js...'
-python ../v1_0/rgbify_hex_vars.py --filter-prefix=google --replace \
+python rgbify_hex_vars.py --filter-prefix=google --replace \
     components-chromium/paper-styles/color.js
 
 # TODO create components summary
 
 echo 'Creating GN files for interfaces and externs...'
-../v1_0/generate_gn.sh 3 # polymer_version=3
+./generate_gn.sh
diff --git a/third_party/polymer/v1_0/rgbify_hex_vars.py b/third_party/polymer/v3_0/rgbify_hex_vars.py
similarity index 100%
rename from third_party/polymer/v1_0/rgbify_hex_vars.py
rename to third_party/polymer/v3_0/rgbify_hex_vars.py
diff --git a/third_party/polymer/v1_0/rgbify_hex_vars_test.py b/third_party/polymer/v3_0/rgbify_hex_vars_test.py
similarity index 100%
rename from third_party/polymer/v1_0/rgbify_hex_vars_test.py
rename to third_party/polymer/v3_0/rgbify_hex_vars_test.py
diff --git a/tools/polymer/generate_gn.py b/tools/polymer/generate_gn.py
deleted file mode 100755
index 96413fab995f4a..00000000000000
--- a/tools/polymer/generate_gn.py
+++ /dev/null
@@ -1,86 +0,0 @@
-#!/usr/bin/env python
-# Copyright 2017 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-from __future__ import print_function
-
-from bs4 import BeautifulSoup
-from datetime import date
-import os.path as path
-import sys
-
-_COMPILE_JS = '//third_party/closure_compiler/compile_js.gni'
-_POLYMERS = ['polymer.html', 'polymer-mini.html', 'polymer-micro.html']
-_COMPILED_RESOURCES_TEMPLATE = '''
-# Copyright %d The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-#
-# NOTE: Created with %s, please do not edit.
-
-import("%s")
-
-%s
-'''.strip()
-
-
-def main(created_by, html_files):
-    targets = ''
-
-    def _html_to_extracted(html_file):
-        assert html_file.endswith('.html')
-        return html_file[:-len('.html')] + '-extracted'
-
-    def _target_name(target_file):
-        return _html_to_extracted(path.basename(target_file))
-
-    def _has_extracted_js(html_file):
-        return path.isfile(_html_to_extracted(html_file) + '.js')
-
-    html_files = filter(_has_extracted_js, html_files)
-
-    for html_file in sorted(html_files, key=_target_name):
-        html_base = path.basename(html_file)
-        if html_base in _POLYMERS:
-            continue
-
-        parsed = BeautifulSoup(open(html_file), 'html.parser')
-        imports = set(
-            i.get('href') for i in parsed.find_all('link', rel='import'))
-
-        html_dir = path.dirname(html_file)
-        dependencies = []
-        externs = ''
-
-        for html_import in sorted(imports):
-            import_dir, import_base = path.split(html_import.encode('ascii'))
-            if import_base in _POLYMERS:
-                continue
-
-            # Only exclude these after appending web animations externs.
-            if not _has_extracted_js(path.join(html_dir, html_import)):
-                continue
-
-            target = ':' + _target_name(import_base)
-
-            dependencies.append(import_dir + target)
-
-        targets += '\njs_library("%s-extracted") {' % html_base[:-5]
-        if dependencies:
-            targets += '\n  deps = ['
-            targets += '\n    "%s",' % '",\n    "'.join(dependencies)
-            targets += '\n  ]'
-        targets += externs
-        targets += '\n}\n'
-
-    targets = targets.strip()
-
-    if targets:
-        current_year = date.today().year
-        print(_COMPILED_RESOURCES_TEMPLATE % (current_year, created_by,
-                                              _COMPILE_JS, targets))
-
-
-if __name__ == '__main__':
-    main(path.basename(sys.argv[0]), sys.argv[1:])
diff --git a/ui/webui/resources/html/BUILD.gn b/ui/webui/resources/html/BUILD.gn
index b030f490b80a82..5e21e61ec68d46 100644
--- a/ui/webui/resources/html/BUILD.gn
+++ b/ui/webui/resources/html/BUILD.gn
@@ -5,8 +5,6 @@
 import("//build/config/chromeos/ui_mode.gni")
 import("//ui/webui/resources/tools/generate_grd.gni")
 
-include_polymer = !is_android && !is_ios
-
 generate_grd("build_grdp") {
   grd_prefix = "webui_html"
   out_grd = "$target_gen_dir/resources.grdp"
@@ -36,15 +34,11 @@ generate_grd("build_grdp") {
     ]
   }
 
-  if (include_polymer) {
-    input_files += [ "polymer.html" ]
-
-    if (is_chromeos_ash) {
-      input_files += [
-        "i18n_behavior.html",
-        "web_ui_listener_behavior.html",
-      ]
-    }
+  if (is_chromeos_ash) {
+    input_files += [
+      "i18n_behavior.html",
+      "web_ui_listener_behavior.html",
+    ]
   }
   input_files_base_dir = rebase_path(".", "//")
 }
diff --git a/ui/webui/resources/html/polymer.html b/ui/webui/resources/html/polymer.html
deleted file mode 100644
index 6639e7dd54148f..00000000000000
--- a/ui/webui/resources/html/polymer.html
+++ /dev/null
@@ -1,2 +0,0 @@
-<script src="../js/polymer_config.js"></script>
-<link rel="import" href="chrome://resources/polymer/v1_0/polymer/polymer.html">
diff --git a/ui/webui/resources/js/BUILD.gn b/ui/webui/resources/js/BUILD.gn
index 2fe0c9f0017256..caa8f78f7e3e25 100644
--- a/ui/webui/resources/js/BUILD.gn
+++ b/ui/webui/resources/js/BUILD.gn
@@ -100,7 +100,6 @@ preprocess_if_expr("preprocess_src") {
       "i18n_template_no_process.js",
       "list_property_update_behavior.js",
       "parse_html_subset.js",
-      "polymer_config.js",
       "promise_resolver.js",
       "web_ui_listener_behavior.js",
     ]
diff --git a/ui/webui/resources/js/polymer_config.js b/ui/webui/resources/js/polymer_config.js
deleted file mode 100644
index 3433f39d0de693..00000000000000
--- a/ui/webui/resources/js/polymer_config.js
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-if (typeof Polymer === 'undefined') {
-  Polymer = {
-    dom: 'shadow',
-    lazyRegister: true,
-    legacyOptimizations: true,
-    preserveStyleIncludes: true,  // Only matters when using polymer-css-build.
-    suppressBindingNotifications: true,
-    suppressTemplateNotifications: true,
-    useNativeCSSProperties: true,
-  };
-} else {
-  console.error('Polymer is already defined.');
-}