Abstract: The separation of stable isotope carbon-13（¹³C） is very difficult because the separation coefficient is only 1.007. So it is necessary that nearly three thousand theoretical stages should be required to obtain a high abundance product of 99 atom% ¹³C. In order to effectively reduce the difficulty of engineering implementation, it is necessary that high-efficiency packing should be used in the separation of ¹³C. In this paper, the mass transfer analysis of the self-developed high-ratio surface efficient structured packing PACK ¹³C was carried out by means of computational fluid dynamics（CFD）, which was for accurately predicting the mass transfer performance of cryogenic rectification for ¹³C separation. A kind of CFD calculation method for coupling mass transfer efficiency that the mass transfer performance of the entire column was extended from the simulation of the local rectification unit was established, which was obtained by the study on the mutual mass-transfer of gas-liquid two-phase inside the rectification unit consisting of two sheets of packing sheets. The results showed that the calculated mass transfer simulation values were in good agreement with the mass transfer experimental values of ¹³C isotopes separated by cryogenic rectification. The average relative error between the simulated value and the experimental value of the equivalent plate height (HETP) was 10.15%, and the average relative error of the separated work was 9.1%. This research method can be applied to the mass transfer performance prediction of ¹³C industrialization equipment.