The invention provides a urinating room in an underground garage of a high-rise residential building. The urinating room is built in the vacant position of a staircase of the underground garage; a safety door is arranged outside the urinating room; an air exchange system directly connected with a roof is arranged in the urinating room; and urine passes through a treatment pond and then is discharged into a water collecting well of the underground garage. The urinating room in the underground garage of the high-rise residential building is characterized in that the urinating room is arranged ina crossing vacant frame of an upper stair and a lower stair in the staircase of the underground garage of the high-rise residential building; a space is reserved between the urinating room and the stairs and allows for going-into and going-out of the crossing vacant frame; an access of the urinating room is provided with the safety door, a urine pond and an air exchange opening are formed in theurinating room, and a pipeline connected with the air exchange opening is arranged at the edge of the staircase to be directly connected with the roof; and the access of the urinating room communicates with an elevator waiting hall through a channel of the staircase.