A simple silicon microlens array manufacturing technology based on silicon micromachining technology compatible with MEMS process was developed in this paper. The photoresist hot melt method and plasma etching method were used to fabricate silicon microlens arrays of different sizes on silicon wafers. In the experiment, the hot melt technology and etching technology in the process of lens fabrication were studied deeply. Finally, the optimum technological parameters were determined, and the silicon microlens array with diameter of 20~90 μm and high surface quality was prepared.