Abstract: The fractionation process for the mixture of propylene and propane was simulated by modeling the process with industrial operation data. Based on the established model，operation variables and control variables that influence the stability of industrial process were investigaed，such as volume concentration of feed，impurity concentration in product，reflux ratio and feed charge，through which relevant suggestions were proposed. Firstly，the optimum feed stage should be adjusted with the change of feed. Secondly，the controlled propane concentration in propylene production should be in the range between 3000 mL/L and 5000 mL/L，and accordingly，the reflux ratio should be in the range between 14 and 12.5. Finally，propylene concentration in the bottom product should be adjusted between 2% and 6% depending on the feed charge.