Microstereolithography(MSL) technology is derived from the conventional stereolithography process and can meet the demands for fabricating complex 3-D microstructures with high resolution. This technology can be divided into scanning and projection methods, which have different levels of precision and fabrication speeds. Scanning MSL fabricates very fine 3-D microstructures by controlling the position of the laser spot on the resin surface. Projection MSL quickly fabricates one layer with one exposure using a mask. In this paper, we propose a projection MSL system with uniform illumination and image formation based on optical design for fabricating microstructure arrays. This system can realize mass production of 3-D microstructures in the meso-range, which falls between micro- and macro-ranges, with a resolution of a few microns. Microstructure arrays were fabricated to verify the performance of the proposed system.