Abstract: For exploring the mechanism of formation of density solitons and self-generated magnetic field in laser plasma,their evolution is numerically simulated by using of nonlinear equation for density disturbance in axial-symmetric cylindrical coordinate.The simulation results show that laser with intensity of 4×1014W/cm2 irradiation on target produces solitons with density disturbance rate of 82%.At the same time,self-generated magnetic field about 30T along the propagation axes is induced.These results are consistent with observed results.