The invention relates to a method for storing and using underground high-salinity mine water of coal mine. The method comprises the following steps: adopting an underground sump for collecting the mine water generated by coal mining; filtering the mine water collected in the underground sump; and performing reverse osmosis treatment on the filtered mine water. According to the method provided by the invention, the high-salinity mine water is changed into low-salinity qualified water in a manner of filtering and reverse osmosis, so that the high-salinity mine water can be widely applied in production and life, the resource is efficiently utilized and the harmful effect of the mine water draining to the environment is eliminated.