Abstract: This paper aims to improve the surface quality of microfluidic chips, and to develope optimization research on key process parameters of magnetic polishing microfluidic chips. First, a single-factor experimental group was designed. According to the experimental results, the influence law of the key process parameters of magnetic polishing on its polishing quality is that as the polishing gap decreases, the surface roughness of the chip improves from 0.327 μm to 0.045 μm, and then is reduced to 0.130 μm, and the optimal polishing gap is 1.5 mm. The spindle speed affected the torque of the magnetic polishing and the centrifugal force of the polishing medium, however, its effect on the polishing quality was not significant. The surface roughness of the chip remained at 0.045-0.055 μm after polishing by changing the speed and the optimal speed was 400-800 r/min. The surface roughness of the microfluidic chip improved with increasing polishing time, and the highest surface roughness was 0.018 μm. In contrast, the optimal polishing time was 30 minutes. Additionally, the polishing quality of MCF was most affected by the machining gap, and the polishing time was slightly greater than the spindle speed. The experimental results show that by optimizing the key process parameters of magnetic polishing, the surface roughness of the microfluidic chip can increase from 0.510 μm to 0.018 μm, which can further explore the application of magnetic polishing technology to microfluidic chips definite polishing.