diff --git a/manifests/cache.pp b/manifests/cache.pp
index fa7645a7e..daf59ae94 100644
--- a/manifests/cache.pp
+++ b/manifests/cache.pp
@@ -17,6 +17,11 @@
 #   (integer value)
 #   Defaults to $facts['os_service_default']
 #
+# [*backend_expiration_time*]
+#   (Optional) Expiration time in cache backend to purge expired records
+#   automatically.
+#   Defaults to $facts['os_service_default']
+#
 # [*backend*]
 #   (Optional) Dogpile.cache backend module. It is recommended that
 #   Memcache with pooling (oslo_cache.memcache_pool) or Redis
@@ -243,6 +248,7 @@
 class keystone::cache(
   $config_prefix                        = $facts['os_service_default'],
   $expiration_time                      = $facts['os_service_default'],
+  $backend_expiration_time              = $facts['os_service_default'],
   $backend                              = $facts['os_service_default'],
   $backend_argument                     = $facts['os_service_default'],
   $proxies                              = $facts['os_service_default'],
@@ -306,6 +312,7 @@ class keystone::cache(
   oslo::cache { 'keystone_config':
     config_prefix                        => $config_prefix,
     expiration_time                      => $expiration_time,
+    backend_expiration_time              => $backend_expiration_time,
     backend                              => $backend,
     backend_argument                     => $backend_argument,
     proxies                              => $proxies,
diff --git a/releasenotes/notes/cache-backend-expiration-time-9a2b537bcf972708.yaml b/releasenotes/notes/cache-backend-expiration-time-9a2b537bcf972708.yaml
new file mode 100644
index 000000000..e68804aa4
--- /dev/null
+++ b/releasenotes/notes/cache-backend-expiration-time-9a2b537bcf972708.yaml
@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    The new ``keystone::cache::backend_expiration_time`` parameter has been
+    added.
diff --git a/spec/classes/keystone_cache_spec.rb b/spec/classes/keystone_cache_spec.rb
index 8f17662fa..3013b6343 100644
--- a/spec/classes/keystone_cache_spec.rb
+++ b/spec/classes/keystone_cache_spec.rb
@@ -20,6 +20,7 @@ describe 'keystone::cache' do
         is_expected.to contain_oslo__cache('keystone_config').with(
           :config_prefix                        => '<SERVICE DEFAULT>',
           :expiration_time                      => '<SERVICE DEFAULT>',
+          :backend_expiration_time              => '<SERVICE DEFAULT>',
           :backend                              => '<SERVICE DEFAULT>',
           :backend_argument                     => '<SERVICE DEFAULT>',
           :proxies                              => '<SERVICE DEFAULT>',
@@ -66,6 +67,7 @@ describe 'keystone::cache' do
         {
           :config_prefix                        => 'prefix',
           :expiration_time                      => 3600,
+          :backend_expiration_time              => 7200,
           :backend                              => 'oslo_cache.memcache_pool',
           :proxies                              => ['proxy01:8888', 'proxy02:8888'],
           :enabled                              => true,
@@ -118,6 +120,7 @@ describe 'keystone::cache' do
         is_expected.to contain_oslo__cache('keystone_config').with(
           :config_prefix                        => 'prefix',
           :expiration_time                      => 3600,
+          :backend_expiration_time              => 7200,
           :backend                              => 'oslo_cache.memcache_pool',
           :backend_argument                     => '<SERVICE DEFAULT>',
           :proxies                              => ['proxy01:8888', 'proxy02:8888'],