Analysis of the scientific and technical literature shows that there are quite a few methods of mine water processing. Reagent methods can be considered as the most promising and economically expedient. Mine waters are characterized by a high content of hardness ions and sulfates. The concentration of sulfates varies between 5-35 mg-eq/dm3, hardness – 10-40 mg-eq/dm3. It has been established that effective purification of water from sulfates can be achieved with the use of lime and 5/6 aluminum hydroxochloride. The efficiency of the process depends on the doses and ratio of reagents. The degree of softening and purification of water from sulfates increases with an increase in the dose of aluminum coagulant within certain limits. When using 5/6 aluminum hydroxochloride, the efficiency of water purification from sulfates is quite high and small amounts of chlorides are introduced into the water with the coagulant.