In order to meet the requirements of ultra high speed and long distance transmission in wavelength division multiplexing systems,it is necessary to minimize the damage caused by nonlinear effects such as four wave mixing that affect spectral efficiency and system performance.In this paper,a method is proposed to suppress the four wave mixing effect in wavelength division multiplexing optical networks based on the mechanism of four wave mixing.This method determines the individual and combined effects of the first,second,and third optimization priority parameters(such as effective area,channel spacing,and fiber input power)on the four wave mixing effect with or without pre chirp,and performs numerical calculations on the system bit error rate to analyze system performance.In 16 channel system,as the effective area increases,input power decreases,and channel spacing increases,the four wave mixing effect in the fiber optic is reduced,and the four wave mixing effect decreases even lower under pre chirp conditions.When the pre chirp is 800ps/nm,the optimal combination of three parameters results in a minimum bit error rate of 8.16×10 -23 in the channel compared to fiber optic communication systems without parameter optimization and pre chirp,the performance of the system is improved by 132.8 dB.Finally,this work indicates that the proposed parameter optimization strategy based on pre chirp is an ideal solution for optimizing the performance of dense wavelength division multiplexing systems.