Based on monolithic internal body oil circuit of tilt self-locking valve plates in the process of operation of forklift as the research object, the formation of parameters of pressure and flow characteristic when tilt self-locking valve of the valve core displacement with different oil mouth on and off were established, and then analyzed with simulation. The simulation data were compared with theoretical calculation data. The analysis result shows that the trend of theoretical calculation is basically identical to the numerical simulation. The body internal flow model is improved perfectly, and the modeling accuracy is verified, which helps optimization design of element local structure.