Abstract: The wavelengths of 1064 nm and 532 nm of the pulsed Nd: YAG laser were used to irradiate the fused silica to study the interaction between different wavelengths of laser with fused silica. The laser induced damage characteristics in fused silica surface were researched under separate of simultaneous irradiation of 1064 nm and 532 nm wavelengths. Testing the damage probability under different energy density, we obtained the damage probability curves and typical damage morphologies. The results show that the initial damage threshold under simultaneous irradiation with 1064 nm and 532 nm is always less than that under single wavelength irradiation. Add a certain amount of 532 nm laser to 1064 nm laser, fused silica improves the absorption efficiency for 1064 nm. The damage density of fused silica increases under double wavelength simultaneous irradiation. The reason is that the surface defects of fused silica have different absorption mechanisms for different wavelengths.