Gas-water separation ventilation device capable of being closed in cabin

The utility model discloses a gas-water separation ventilation device capable of being closed in a cabin, and relates to the field of ships. Comprising a shell located above a cabin top plate and an internal air duct connected to the lower end of the shell, an air inlet is formed in the upper portion of the shell, an arc part facing the advancing direction of a ship is arranged on the rear portion of the air inlet, a water baffle is arranged in the lower portion of the shell, a plurality of drain holes are formed in the lower portion of the shell, and the lower end of the shell is connected to the cabin top plate. The internal air duct comprises a weather tight closing cover and an air duct, the upper end of the air duct is inserted into the bottom of the shell, an upper opening extends into the shell, the lower end of the air duct is located in the cabin, the weather tight closing cover is located at the upper opening of the air duct and connected with a threaded pull rod in the air duct, and the lower end o