Abstract: The results of the classification of hydrogeological types in coal mines are relatively inadequate to reflect the characteristics of water hazards such as water sources and water inrush channels. It is not very instructive to carry out water control work in coal mines starting from the basic elements of mine water hazard formation, this paper analyses the characteristics and harm degree of mine water hazard under different types of mine water sources, water inrush channels and their combination conditions, the water inrush source can be divided into 4 types according to its water-rich degree and supply capacity:weak supply of slow seepage, fast supply of gushing, strong supply of sudden outflow and non-blocking full supply. The channel of water inrush can be divided into 4 types according to its unblocked degree:low seepage flow, high seepage flow, small sectional free flow pipeline and large sectional free flow channel. Moreover, according to the combination relationship between different water source and water inrush channel, the mine water threat degree is divided into 4 grades:slight, medium, serious and extremely serious. Based on Piper's trilinear chart and Kurlov's principle of groundwater chemical analysis, this paper puts forward the method of water hazard type classification, disaster degree evaluation and the naming according to the "4-4-4" trilinear chart which is more instructive to mine water hazard prevention and control.