Nzg-31II internal combustion rail drilling machine is a special machine suitable for drilling rail fishplate bolt holes in railway engineering and construction departments. It is suitable for drilling holes in P65 and P75 rails. It uses a small gasoline engine as the power, which is decelerated by a special reducer to drive the drill rod to rotate. The handle drives the gear and rack to achieve feeding, and the worm gear mechanism is clamped. A drill rod bracket is provided to ensure the accuracy of the drilling direction and extend the service life of the drill bit, and it is equipped with a special hollow drill bit. Therefore, this machine has the advantages of novel structure, small size, light weight, high efficiency, convenient clamping, and accurate drilling.