Abstract: A coupling optimization design and experimental study method with uniform experimental and Aspen process simulation was established in this paper, which was used for stable isotope ¹³C separation of the double-stage cascade. Based on the above method, the optimization operating parameters were received. The coupling optimization simulation value showed good agreement with the experimental dates, and the average relative error was only 6.5%. On the other hand, compared with the initial test result, the ¹³C abundance of optimized experimental was 14.1%, and the actual growth rate of ¹³C abundance was more than 25%. More importantly, The optimization experimental did not increase energy consumption. The method confirmed by the experiment could provide a solid foundation for the cascade process of ¹³C industrialization, and it could also be applied to other traditional distillation industry.