Propylene distillation column is an important product separation unit for ethylene plant. The original automatic control mode of propylene distillation column could not satisfy the requirements of stable operation of the unit under high load, and there was a great propylene loss at the bottom of the column. Through the application of advanced process control (APC) technology, the operation of propylene distillation tower was adjusted and optimized, the propylene loss in the tower kettle was reduced, the fluctuation in pressure, liquid level, flow rate, sensitive plate temperature and propylene content in tower kettle of the tower system was minimized, and the system could be operated rapidly in the optimal operation area, thus meeting the requirements of stable operation, high efficiency, energy saving, consumption reduction and efficiency improvement under high load.