In order to realize high throughput of Hadamard spectrometer, the performance of four Hadamard S slits are compared. Multi-micro-silicon slits were produced by MEMS technique. Based on diffraction theory, the formula with Hadamard S matrix is presented. The phenomenon of diffraction is analyzed by using the software of Matlab. The comparison was made between the Matlab simulating picture and the actual diffract picture of S slits on throughput. Experiment results indicate the precisions of the system. The influence of the factors such as spot distance, slit dimension and the matrix array on the throughput was analyzed, then the diffracting way of S slit was offered. The results of emulation are consistent with test, and proved that the design method on the slit in the paper is right. The way of analysis can provide some theoretic and application foundations for slit design.