The natural frozen experiment on the water from Wuliangsuhai lake shows that the pollutants migrate from ice body to water body during the freezing process, which means that freezing process has a good purification effect on pollutants in water environment. The experiment also shows that the removal efficiency of pollutants rises at first and then decreases as the ice thickness increases. At 15cm thickness, the removal efficiency of total dissolved solids(TDS), ammonia nitrogen (NH3-N) and chemical oxygen demand (COD) can reach 81.20%, 86.80% and 86.60%.What is more, the removal efficiency is better as the frozen stage increase. The removal efficiency of TDS, NH3-N and COD is more than 92% through three stages frozen. Drawing inspiration from the natural frozen experiment and its mechanism of frozen concentration effect, a tentative idea that natural cool energy can be applied in the non-centralized water supply field was put forward and a reasonable technological process of freezing purification was designed, which can not only improve the quality of drinking water in rural area, but also can reduce the drinking water processing cost.