An embodiment of the utility model provides a water drainage and gas collection device, include: the upper portion and the one end of gas injection device of gas recovery pipe post are connected, and the lower part and gas -liquid diverging device's the upper portion of gas recovery pipe post are connected, the gas recovery pipe post is located the inside of column pipe, is provided with default distance between the bottom of column pipe and packer to formation is used for the breach of drainage, inside column pipe, gas -liquid diverging device and liquid leading pipe lie in the sheathed tube, and the sleeve pipe is provided with the perforation in the well section that lies in the gas -bearing formation position, the sleeve pipe top is equipped with to annotate adopts the mouth, and the one end and the notes of gas injection device are adopted the mouth and are connected, gas -liquid diverging device's lower part is connected with liquid leading pipe's upper portion, has formed sealedly between gas -liquid diverging device and the sleeve pipe through the packer to space separation becomes first portion space and second portion space with the sheathed tube annular, liquid leading pipe's lower part and check valve are connected, and liquid leading pipe is used for the liquid water conservancy diversion in the hydrops district to the sheathed tube first portion space in. The utility model discloses can improve gaseous extraction rate.