diff --git a/lib/trello/board.rb b/lib/trello/board.rb
index <HASH>..<HASH> 100644
--- a/lib/trello/board.rb
+++ b/lib/trello/board.rb
@@ -26,7 +26,7 @@ module Trello
       attribute :url, readonly: true
       attribute :short_url, readonly: true, remote_key: 'shortUrl'
       attribute :prefs, readonly: true
-      attribute :last_activity_date, readonly: true, remote_key: 'dateLastActivity'
+      attribute :last_activity_date, readonly: true, remote_key: 'dateLastActivity', serializer: 'Time'
       attribute :description_data, readonly: true, remote_key: 'descData'
       attribute :enterprise_id, readonly: true, remote_key: 'idEnterprise'
Set serializer to Board#last_activity_date