采用分步傅里叶法研究了三阶非线性色散项对超短脉冲传输的影响.通过模拟数值计算得出，在德鲁德模型频率选取的一定范围内,三阶非线性色散项对超短脉冲传输所造成的影响是不可忽略的.结果表明:三阶非线性色散项系数取负值时，在正常色散区超短脉冲不对称展宽，脉冲中心向前沿偏移; 在零色散点超短脉冲不对称展宽程度加剧并在脉冲前沿形成振荡，脉冲中心向前沿偏移; 在反常色散区超短脉冲不对称变窄，脉冲中心仍向前沿偏移.

The split-step Fourier method is used to simulate the impact of ultra-short pulse with third-order nonlinear dispersion.In the frequency of Drude model of selecting certain range,the impact of third-order nonlinear dispersion to ultra-short pulse can not be ignored by numerical calculating.When third-order nonlinear dispersion is negative,the results show that in the normal dispersion,ultra-short pulse is wide asymmetric and pulse central drifts to the forefront; in zero dispersion,the degree of asymmetry broadening of ultra-short pulse increass and the center of pulse which drifts to the forefront had a oscillation only in the forefront of pulse.In anomalous dispersion,ultra-short pulse is asymmetry narrow,the central of pulse also drifted to the forefront.