Abstract: In order to improve the monitoring ability of floor water during the mining process, the existing mining floor water monitoring system is improved. The ultra-high density resistivity method with multi-channel data acquisition and multi-device data joint inversion is selected to maximize the data acquisition ability and provide more abundant geological information. During the inversion process, smooth and background constraints are applied simultaneously to improve the stability of the inversion. The inversion equation is constructed to introduce a regularization factor to improve the generalization ability of the equation. At the same time, the electrodes and cables buried in the working face roadway boreholes are monitored at a certain interval to obtain the changes in resistivity of the working floor water at different time, and then to obtain the underground water movement. Combined with the periodic change of mine pressure and drilling grouting data, the paper analyzes the reasons of floor water movement, realizes the dynamic monitoring of floor water in the process of coal mining.