Abstract: Stochastic statechart is widely used modeling systems.Lack of consideration of comparability between different sub-systems leads to the complexity of modeling.Stochastic statechart is improved by using abstract sub-system and general system chart to express the comparability and integrity of stochastic statechart respectively.The performance measurements can be obtained by the Continuous-Time Markov Chain,which is transformed from the manufacturing system model by the improved stochastic statecharts.A case study shows that the improved stochastic statechart can effectively simplify the modeling and performance evaluation process and it is useful to configuration and optimization of manufacturing system.