Based on the hydrochemical test data of mine water, this paper studied the hydrochemical genetic mechanism of mine water source in Chensilou Coal Mine by systematic cluster analysis and Bayesian discriminant method, clarified the hydrochemistry source and composition of mine water, and found out the hydrochemistry causes of the main water source of the mine. The results showed that the hydrochemistry characteristics of each aquifer were significantly different. Based on the analysis of the variation coefficient hotspot map, the results showed that K++Na+, Ca2+, Mg2+ and HCO3- had a large variation coefficient, which was a positive factor of hydrochemistry process. The correlation analysis showed that there were significant differences in the composition of limestone water and sandstone water in the mine field, and they had certain homology with surface water samples. The correlation type combination of elements in goaf water had certain similarity and difference with sandstone fissure water and limestone fissure water, which was consistent with its source. The results of the systematic cluster method showed that the overall independence of the aquifer in Chensilou Coal Mine was strong, and only two adjacent aquifers were similar in local area. According to the Gibbs diagram of groundwater in Chensilou mine field, the surface water, limestone water and sandstone water around Chensilou mine field were mainly located in the area of water slow alternation action. The composition of groundwater was mainly controlled by evaporation and concentration, among which the effect of evaporation and concentration of limestone water and sandstone water was not much different, while the degree of evaporation and concentration of surface water was different in time and space.