Expounds the basic concept, technical regulations and program modules of OPC, introduces the application and development approaches of OPC technology in view of currently used developing platform and provides three different types of engineering application. Through the choice of developing ways at different platforms and combination with specific project examples, compares the different developments of OPC technology, enhances the understanding of engineering and technical personnel to OPC technology-related knowledge and the applied developing methods, and provides a reference for the application and development of OPC technology.