The electrical model and nonlinear characteristics of the silicon photovoltaic (PV) cell are analyzed in this paper. The SIMULINK simulation model is built based on the output characteristics of single PV cell. The common methods of maximum power point tracking (MPPT) are comparatively studied. An improved method based on the traditional incremental conductance method is simulated and studied. Simulation results indicate that PV cell model can simulate the electrical characteristics of PV cell in various in solation and temperature, the improved method can adapt to rapid changes in temperature and in solation and track the maximum power point much better than the traditional methods in speed and stabilities.