diff --git a/Gemfile b/Gemfile
index 6683d70df..af5aa679a 100644
--- a/Gemfile
+++ b/Gemfile
@@ -13,7 +13,7 @@ gem 'share_notify', '~> 0.2.0'
 #gem 'solrizer-fedora', '3.0.0.pre1' # PRE-LOCK
 gem "solrizer-fedora", github: 'ucsdlib/solrizer-fedora', ref: '87c2d35e'
 
-gem 'sitemap_generator', '~> 5.3.1'
+gem 'sitemap_generator', '~> 6.0.0'
 
 gem 'sqlite3', '~> 1.3.13'
 
diff --git a/Gemfile.lock b/Gemfile.lock
index d5794666d..b206e4873 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -376,7 +376,7 @@ GEM
       json (>= 1.8, < 3)
       simplecov-html (~> 0.10.0)
     simplecov-html (0.10.0)
-    sitemap_generator (5.3.1)
+    sitemap_generator (6.0.0)
       builder (~> 3.0)
     slop (3.6.0)
     solrizer (3.1.1)
@@ -482,7 +482,7 @@ DEPENDENCIES
   selenium-webdriver (= 3.4.0)
   share_notify (~> 0.2.0)
   simplecov (~> 0.14.1)
-  sitemap_generator (~> 5.3.1)
+  sitemap_generator (~> 6.0.0)
   solrizer (~> 3.1.0)
   solrizer-fedora!
   sprockets (~> 2.12.4)