It is very important for practicability and system designing to study on the optical soliton transform and evolution with numerical simulation. In this paper, the split-step Fourier transform method (SSFM) is particularly introduced and the simulation is also given. The Matlab language is used to simulate the soliton propagation in the optical fiber. The influence of optical fiber waste is discussed and it also pointed that if two optical solitons is very near, they will strongly infect each other, it can make the soliton shape aberrant.