The operation of manufacturing systems can be effectively monitored through analysis and measurement of the information of various states of manufacturing systems. Based on analyzing the trait of dissipative structure of manufacturing systems, a sketch of dissipative structure of manufacturing systems is shown. By the correlation between control variables and state variables of cusp catastrophe theory, a dissipative structure model is established, making it possible to quantitatively determine when manufacturing systems may form dissipative structure. According to the definition of the information entropy of manufacturing systems, the models of expected state entropy, and actual state entropy are built up, respectively, thus serving the purpose of exactly assessing the operational states of the systems by the model of dissipative structure. Taking a job shop of implementing cellular manufacturing as an example, using established dissipative structure model and its solved method, this paper quantitatively determines whether the manufacturing systems may form dissipative structures under two different states. The result fairly validates the reasonableness of this method and also provides an effective approach for the optimization of manufacturing systems.