In order to solve the mesh distorted problem, which is caused by large deformation, in simulation of linear shaped charge jet by traditional mesh based method, the self code of SPH method is applied to simulate the formation process of linear shaped charge jet and its subsequent penetration process of metal plate. The SPH method implemented in this paper can be taken as an alternative method for numerical study of linear shaped charge jet. Firstly, the numerical model of linear shaped charge jet based on experiment has been constructed and simulated by SPH method. The jet formation process of linear shaped charge has been simulated successfully by SPH method. Comparing numerical result with experiment data, the error of jet head velocity is less than 10%. Then, the jet formation processes of linear shaped charge with different liner but the same of charge mass, liner mass and width of charge cross section have been studied by numerical simulation. The penetration of metal plate by linear shaped charge jet has also been simulated. Through the numerical analysis, the forming characteristics of linear shaped charge jet, the time history of cutting width and penetrated depth of metal plate are obtained. The regularity of the formation and subsequent penetration process of linear shaped charge jet with different liner obtained in this paper can provide references for the design of linear shaped charge jet.