In order to detect the drinking water quality in our country at the present time effectively, several brand brands of drinking water on the market and the distilled water that laboratory offered were measured and calculad were measured and calculated. The laser Raman spectra of samples were measured, while the sample's degree of degeneracy polarization at the symmetric stretching peak was calculated from the measurements. Results indicate that the relative intensity of the Raman spectrum and the degree of degeneracy polarization follow the same rule. Through comparison and analysis of the results of measurement and calculation, it is concluded that we can judge the relative content of mineral substance of drinking water by comparing the strengths of laser Raman spectrum characteristic peak and the magnitudes of the sample's degree of degeneracy polarization at the same characteristic peak. This conclusion will provide us a new and effective path to assaying the quality of drinking water.