In this paper the steady simulation and optimization were carried on for the synthesis of oxalate by carbon monoxide coupling-regeneration reaction in the gaseous phase with sequential modular approach modification software ASPEN, PRO/? and programs about two-dimension quasi-homogeneous reactor and gas-liquid bubble column reactor. At the same time, the influence of various operating parameters were investigated and the optimal operation range was determined. As well as the significance test about the simulation results and experimental results were carried out and the belief level is 95%.