In the evaluation of solar cell efficiency, the cell material, doping concentration, diffusion length and so on are important parameters. Reasonable change of relevant parameters can optimize the performance of solar cells and improve their efficiency. In addition, there is an important means to improve the efficiency of solar cells by coating a layer of antireflection optical film on the surface of solar cells. To improve the cell efficiency, the micro parameters such as doping concentration and diffusion length of monocrystalline silicon solar cells were calculated and optimized, and the changes of cell efficiency with doping concentration and diffusion length were analyzed. On this basis, the influence of different antireflection films on the efficiency of the battery is analyzed, and the influence of antireflection film thickness on the efficiency of the battery is given. The results show that after optimizing the doping concentration and diffusion length of the cell, and selecting suitable antireflection films, the cell efficiency can reach 20.35%, which is 8.25% higher than that without optimization.