Abstract: Aspen Plus can effectively simulate chemical processes and achieve the optimization of functions,sensitivity analysis,and cost estimation.However,the shortcoming of Aspen Plus is that it doesn't provide all the unit models for complex chemical processes.In this work,we develop a user interface model of AEM between Aspen Plus and Matlab by means of the data exchange function between Aspen Plus and Matlab,which can directly use Matlab program in Aspen Plus user interface to build a unit model based on soft-sensor.Finally,by using the proposed user model and GPR multi-model soft-sensor,the user model of the crystal tower in a production process of bisphenol A is developed and the simulation of the adduct crystallization process is realized.Moreover,the user model is also used in the production process simulation of bispheonl A.