Knowledge extraction and representation are the two most important problems to build up expert systems. This paper describes an example of a knowledge based prototype Hi-KJBIPP, which is designed in a hierarchical architecture to express different levels of machining knowledge for complex box-type workpieces. Production systems and frames are both used as knowledge representation methods in Hi-KBIPP. A production rule system is used to represent top levels of knowledge, in which the control strategies that consist of priority classification, priority execution, and context restriction are designed to decide the first rule to be executed when several rules are of the same qualification. Frames are used to represent the information of machining procedures. A particular frame system is used in Hi-KBIPP which provide multi-dimension frame, similarity network, and associate-network to handle and compile knowledge.