Abstract: Aiming at the problems of poor detection accuracy and low efficiency of roof and floor interface in horizontal well drilling in coal mine, the design idea of explosion-proof azimuth electromagnetic wave logging tool while drilling in coal mine is put forward. In order to suit the working environment of underground coal seam, the influence of instrument parameters such as source distance, transmitting frequency and coil installation angle on signal response was obtained by forward simulation. The results show that the received signal strength of the azimuth electromagnetic wave instrument while drilling increases with the increase of transmitting frequency, coil distance and formation resistivity contrast; When the coil installation angle is about 45 degrees, it satisfies not only the sensitivity of the received signal, but also the intensity of the signal; the optimum working frequency band of the instrument is 100 kHz to 1 MHz. Through the simulation study of the response of azimuth electromagnetic wave logging while drilling tool, the selection basis for the parameter optimization de-sign of underground instrument in coal mine is provided, and the changing law of the interface response of coal and rock roof and floor is mastered. The application of this tool will improve the detection accuracy and efficiency of roof and floor detection.