Abstract: Water injection is an effective measure to reduce the rock burst tendency and risk level in coal mines. Laboratory field research shows that the consistent coefficient and uniaxial compressive strength of coal sample decreased with increasing time after the immersion test. And the drilling cuttings weight and electromagnetic radiation strength of coal seam with water injection decreased significantly on site. For judging the infusibility of coal seam infusion, six influencing factors including cranny viability, porosity, wet rim angle, firm coefficient, saturation moisture increment and buried depth were selected as evaluation indexes, and four discriminant functions were obtained through training 15 studying samples from different mining areas coal mines and the ratio of mistake-distinguish was zero after the distance discriminant analysis (DDA) model was trained. Coal sample seam of Dongrong 2 coal mine from a coal mine was used to verify this model. The results show that the DDA model is an effective method to judge the infusibility of coal seam infusion.