The application provides a downhole electric drilling tool for gas drilling and an application method thereof, wherein the downhole electric drilling tool comprises a
drill string joint, a
power unit, a transmission unit and a
drill bit, the
drill string joint is fixedly connected to the upper end of the
power unit, and the
drill string joint is used for connecting the electric drilling tool with an upper
drill string; the transmission unit and the
drill bit are sequentially connected to the lower end of the
power unit, the power unit comprises a power supply
assembly and a motor, the power supply
assembly is connected with the motor, and the power supply
assembly can provide power for the motor; the transmission unit comprises a speed
reducer, the speed
reducer is connected between the motor and the
drill bit, and is used for transmitting the
power output by the motor to the
drill bit to drive the drill bit to drill. The application adopts a mode that high-density storage batteries directly supply power to the electric drilling tool, and then a planetary
reducer is used to obtain the torque required for sliding drilling of gas drilling, and the
driving mode of a gas screw is abandoned, and the operation capacity and reliability are greatly improved.