Aspen Adsorption is a comprehensive flowsheet simulator developed for the optimal design, simulation, optimization and analysis of adsorption processes. Foreign scholar A. E. Rodrigues[1～2] et. al simulated the variation of energy and concentration in the PSA process. In the domestic, D. H. Zhang[3] proposed a three bed VPSA process used to separate the mixed gas methane-nitrogen, and the concentration of methane increased from 30% to 60%. In this study, Aspen-Adsim has been used to simulate the separation of paraffins. A Aspen-adsim simulation model had been developed for single adsorption tower according to the technology of PSA separation of light naphtha. Model parameters including equilibrium isotherms, kinetic parameters and energy balance equations were got from correlative literatures and independent experiments in our laboratory. Aspen-Adsim software was used to simulate the breakthrough of n-paraffins in single bed using those parameters, and the results were compared with experiment. The results show high purity iso-paraffins （≥95.5%wt） and n-paraffins （≥99.5%wt ） products are gained. The simulated results are in good agreement with the experimental results, and the deviation values between simulation and experiment are less than 7%.It provides basic design parameters for the setup of industrial plants.