Web services technology has emerged as a key infrastructure that enables business entities to interact with each other without any human inventions. In order for the technology to be widely used, especially in any field where a large volume of transactions may be processed, it is highly desirable that the Web services engine should tolerate such environments. In this paper, we present a novel approach for improving Web services performance. We first focus on the fundamental characteristics of the Web services in that the SOAP messages on the wire are mostly generated by machines and have a lot of similarities among the processed messages. By making use of these features and eliminating the redundant processing, we propose a new deserialization mechanism that reuses matching regions from the previously deserialized application objects from earlier messages, and only performs deserialization for a new region that would not be processed before. Through our experiments in this paper, we observed that our approach obtained a 288% performance gain (maximum) by incorporating the differential deserialization into the Axis SOAP engine.