By properly choosing the parameters of the non-linear Schrdinger equation which satisfies the optical soliton propagation,and by using independent analysis and the comprehensive analysis for the factors such as dispersion and non-linearity which influences Gauss pulses propagation,two conclusions are obtained.The second-order dispersion mainly influences the pulse amplitude but the pulse shape,and the chirp effect is the key factor for the pulse distortion.The chirp,the third-order dispersion and the fifth-order nonlinearity simultaneously influence the pulse propagation,and they also influence and interact with each other.As they approach a certain parameter,the high gain effect and the reshape effect occur in the propagation of the pulse.The improvement method for the characteristics of pulse propagation is theoretically proposed based on the analysis and simulation results,which has theoretical importance for the practice of soliton optical fiber communication.