A control valve for an air cushion bed includes a first main body, a membrane plate, a second main body, a sensor, and a depressurization unit. The membrane plate is clamped between the first main body and the second main body. The second main body at one side of the membrane plate is connected with the sensor. The sensor is used to detect the inputted air pressure. When the air is over, the air can be depressurized by the depressurization unit. The control valve of the present invention is applied to input and control the air of the air cushion bed, having depressurization and air detection functions.