A system based on object-oriented large-grain data flow model, called OOCPCS, is designed to facilitate parallelism in distributed system. Its underlying model of computation is an integrated object-oriented paradigm and large-grain data flow model, called OOLGDFM. It introduces persistent state object and object-oriented features into large-grain data flow model. Its graphs are constructed dynamically. The paper discusses the realization of the model in OOCPCS, the use of forward _ list, parallelizing compiler, POC programming language, object-oriented network file I/O, and the virtual OOLGDFM machine.