1 files changed, 5 insertions, 1 deletions
diff --git a/activerecord/lib/active_record/type/internal/abstract_json.rb b/activerecord/lib/active_record/type/internal/abstract_json.rb
index 513c938088..e19c5a14da 100644
--- a/activerecord/lib/active_record/type/internal/abstract_json.rb
+++ b/activerecord/lib/active_record/type/internal/abstract_json.rb
@@ -17,7 +17,11 @@ module ActiveRecord
         end
 
         def serialize(value)
-          ::ActiveSupport::JSON.encode(value)
+          if value.nil?
+            nil
+          else
+            ::ActiveSupport::JSON.encode(value)
+          end
         end
 
         def accessor