Dynamic simulation which enables to analyze and predict dynamic behavior of process systems as time varies is very important for the design, control and operation of chemical processes. Current dynamic simulation packages are mainly suitable for handling only continuous variables. However few processes can be fully modeled through existing dynamic simulator mainly due to dis- crete changes that affect most systems to a great extent. In this paper, we developed the classification of discrete events arising in chemical process control system for the consistent mathematical modeling. Dynamic simulation examples including all the types of discrete events were solved using gPROMS(General PROcesses Modeling and Simulation). Based on the discrete event handling technique, start-up and shutdown procedures of a batch rea- ction process also studied.