The work aims to meet sealing requirements of safety valve seat and valve disc fitting surface, improve grind repair quality and efficiency of safety valve sealing surface, and make valve seat and disc surface roughness Ra≤0.1 μm. With Al2O3 abrasive paper and white corundum abrasive paste as grinding medium, effects of grain fineness, grinding time, grinding speed and grinding pressure on sealing surface roughness and grinding amount were studied based on orthogonal experiment. Surface roughness, grinding amount and surface morphology of the valve seat and valve disc were measured and analyzed using roughness tester, micrometer and electron microscope. Optimum technological parameters were obtained with grinding amount and surface roughness as evaluation indicators, and reliability of the experiment was verified by multiple repetitive experiments. Provided with optimum grinding technological parameters, the grinding amount of valve seat and valve disc grinded by sandpaper was 0.023 mm, and surface roughness 0.135 μm, surface roughness of valve seat and valve disc polished with abrasive paste was 0.073 μm. Optimum technological parameters for sandpaper grinding are: grinding pressure 80 N, grinding speed 80 r/min, grinding time 10 min, sandpaper fineness 1000 mesh; for abrasive paste polishing: polishing pressure 30 N, polishing speed 100 r/min and polishing time 10 min. Sandpaper and grinding paste grind repair process can improve grinding amount, reduce surface roughness, and improve sealing performance of grinded safety valve.