Aimed at the puzzle of being difficult to carry through the quality traceability for the unqualified products resulted in a great variety of electromechanical products, the paper designed a kind of quality traceability system of electromechanical products based on OPC. In the paper, it pointed out the complexity and technology difficulty of product quality tracing, discussed on the technical specification, the essence of technology, the principle of data exchange and the data access interface, researched on the framework of product quality traceability system, and designed a quality traceability system of electromechanical products based on OPC. Taken the interconnection of monitoring software system as an example, it built the system which demonstrated that the seamless integration of heterogeneous system based on OPC could overcome the puzzle of information islands resulted in device diversity and driver incompatibility. The practice shows that it has a broad prospect of application to the quality traceability system based on OPC.