Abstract: Pinch technology was applied to optimize the heat exchanger network (HEN) for a petrochemical enterprise with a capacity of 1.4 Mt/a FCCU. The results show that the energy consumption of the whole FCCU are decreased by 7.88 t/h of 1.0 MPa steam, 3.77 t/h of circulating water and 16 kW of electricity. And the comprehensive energy consumption of the optimized FCCU is decreased by 109.19 MJ/t, equivalent to the benefit of ￥12.213 million/a.