diff --git a/lib/active_record/connection_adapters/clickhouse/oid/date_time.rb b/lib/active_record/connection_adapters/clickhouse/oid/date_time.rb
index 82232810..909b83d4 100644
--- a/lib/active_record/connection_adapters/clickhouse/oid/date_time.rb
+++ b/lib/active_record/connection_adapters/clickhouse/oid/date_time.rb
@@ -8,6 +8,7 @@ class DateTime < Type::DateTime # :nodoc:
 
           def serialize(value)
             value = super
+            return unless value
             return value.strftime('%Y-%m-%d %H:%M:%S') unless value.acts_like?(:time)
 
             value.to_time.strftime('%Y-%m-%d %H:%M:%S')