Combining with production features of the machining shop in small and medium manufacturing enterprises and difficulties in their information construction, we studied deeply on the scheduling model suitable for complex information environment of the machining shop, and established the job planning and scheduling system model. The hybrid modeling method of UML and IDEF was adopted to describe the architecture of the job planning and scheduling system in machining shop. IDEF, which has good flexibility and logic, is used to describe the system's functions and needs, and then express an implementation scheme that can meet the needs and realize the functions. At the same time, UML is utilized to reflect the chronological relationship of the interaction between functional objects. From the perspectives of structure, function, information and control, both of the above advantages are combined to establish the flexible and reusable model for job planning and scheduling system in machining shop.