In order to improve the perception level of fault water damage in coal mine,a fault water inrush stage sensing method based on fault activation evolution mechanism and key control factors was proposed.The evolution characteristics of working face floor and fault failure were studied through similar simulation tests of fault water inrush evolution process.The stage characteristics of monitoring parameters and the change of water inflow were revealed by taking the stress in the failure zone of floor,the stress in the fracture zone of fault and the water pressure in the water channel as the stage monitoring parameters.The key controlling factors of water inrush phase transformation were determined by grey correlation analysis method.Then,according to the fault water inrush analysis and research process,the fault water inrush stage perception method was proposed.The study determines that the numerical variation characteristics of monitoring parameters such as stress of floor failure zone,fault fracture zone and water pressure in water channel show obvious stage characteristics during fault activation water inrush.The order of grey correlation degree between control factors and water inflow is as follows:stress in floor failure zone>stress in fault fracture zone>water pressure in water channel,through identification of key control factors.Through the identification of key control factors,the perception of fault water inrush stage can be realized,and the perception method based on grey correlation analysis is feasible in principle.