Silver films bedded and covered Al₂O₃ were prepared with five different deposition rates:0.44,0.30,0.18,0.08 and 0.04 nm/s. The reflectance spectra indicated the sample with a deposition rate of 0.18 nm/s had the highest average reflectance. X-ray diffraction (XRD) spectra of the five samples were obtained by XRD,which showed silver (111) was the preferred orientation. The sample with the deposition rate of 0.18 nm/s had the highest intensity of diffraction peak,the narrowest full width at half maximum (FWHM) and the biggest average grain size,which totally meant the sample had a best crystallinity. Samples with faster or slower deposition rate would cause low level crystallinity and resulted in the increase of extinction coefficient and decrease of reflectance. In our experimental conditions,it is suggested the best deposition rate is around 0.18 nm/s,which can lead to the best crystallinity and average reflectance. The result is different from the opinion which originally regarded the quality and reflectance of silver films would be better with faster thermal evaporation deposition rate.