Abstract: Gallium oxide crystal is the most representative fourth generation semiconductor material with the advantages of high band gap, high voltage resistance and short absorption cutoff edge, and has broad application prospects. Gallium oxide crystal is prone to micro-cracks, scratches and other surface defects in the polishing process, which is difficult to achieve high-quality surface processing and cannot meet the requirements of the corresponding devices. Moreover, the existing polishing process of gallium oxide crystal is complex and inefficient. Fixed abrasive polishing technology has the advantages of controllable abrasive distribution and depth of cut, and high utilization rate of abrasive grain. Fixed abrasive polishing was used, and the effect of pad and slurry on material removal rate and surface quality were explored in fixed abrasive polishing of gallium oxide crystal. The results show that when the hardness of the polishing pad is moderate II, the abrasive concentration is 100%, and the slurry additive is oxalic acid, material removal rate is 68 nm/min, and the surface roughness Sa value is 3.17 nm in fixed abrasive polishing gallium oxide crystal. Fixed abrasive polishing technology can achieve efficient and high-quality polishing of gallium oxide crystal