Abstract: In order to successfully combine Zemax′s functions of the optical system design and analysis with Matlab′s powerful ability on the matrix calculation and data analysis, the communication technique of DDE(dynamic data exchange) between the two softwares was researched and applied to the numeric simulation process of the computer-aided resonator alignment. The control of Matlab to Zemax was implemented through DDE and the data transmission between the two softwares was realyzed. In other words, under the cantrol of Matlab, the structure of the optical system can be rectified, and it is easy to get a series of values of Zernike polynomial coefficients of the output beam. So it is convenient for the following data process. In the same way, the calculation results can be sent to Zemax as a feedback of the optical system optimization. Data reliability and work efficiency can be improved in this way. DDE technique between Zemax and Matlab is very helpful in the field of optical system design and optimization.