Abstract: With the increasingly serious energy and environmental problems, solar energy, as a green renewable energy, has been greatly developed. Photovoltaic power generation is the most common form of solar energy utilization, and maximum power point tracking（MPPT） is one of the effective ways to improve the efficiency of photovoltaic power generation. Due to the complex environment of the PV generation system, it is difficult to avoid partial shading conditions（PSCs）, and the traditional tracking algorithm may have misjudgment. Aiming at this problem, the paper takes the MPPT control of photovoltaic array as the main line. The principle of photovoltaic power generation is analyzed, and a 4-series 2-parallel photovoltaic array is built. Through simulation and programming, the output characteristics of arrays under PSCs are explored and the rules are summarized. On this basis, the MPPT is theoretically analyzed, and an effective control method is designed based on particle swarm optimization algorithm, which realizes the maximum power point tracking under PSCs. The PSO MPPT algorithm is simulated by Simulink to verify the feasibility of the proposed algorithm.