Abstract: Poly aluminum chloride（PAC) is a kind of the most widely used and the largest sales inorganic polymer coagulants and water treatment agent.Poly aluminum chloride has many advantages，such as little effect on pH of effluent，less usage，less sludge，and higher efficiency of turbidity removal.Therefore the Chinese had made a lot of researches on the preparation techno- logy and application of poly aluminum chloride.Basing on the different materials，the production status of Chinese PAC was introduced，and the advantages and disadvantages of different preparation methods were analyzed.According to different dosing conditions，i.e.，dosing PAC，dosing compound-PAC，and dosing coagulant aid with PAC，the application status of Chinese PAC was discussed，respectively，then the research and development of poly aluminum chloride in future were forecasted.

Key words: poly aluminum chloride, preparation, application, coagulant, water treatment