Process pattern is an excellent method to express software process knowledge, it can express processknowledge in different granularity and realize the non-gap connection of process knowledge, it supports the reuse andpersistent improvement of process knowledge. In this paper, we put forward a process Pattern Based Software Pro-cess Framework(PB-SPF), its three layer architecture has realized the high abstraction of software process and theseparation of its contents, so it have good reusability and adaptability. We can use it as a base for the research of soft-ware process, the building and enactment of process model.