The invention relates to an integral bathroom chassis side discharge system. The integral bathroom base chassis side discharge system comprises an integral bathroom chassis, a drain pipe and a floor drain. An inner groove for accommodating the drainage pipe is formed in the periphery of the integral bathroom chassis, the floor drain is installed in the integral bathroom chassis in an inlaid mode,and a sinking hole type drain interface penetrating through the integral bathroom chassis in the horizontal direction is formed in one side of the floor drain. A three-way joint is connected to the drain pipe in series, and a joint, located on the side surface of the drain pipe, of the three-way joint is inserted into the drain interface. The integral bathroom chassis side discharge system has thebeneficial effects that a side discharge structure is adopted, the thickness of the integral bathroom chassis and a gap between the integral bathroom chassis and a wall body are used, under the condition of not occupying the original design height, sewage of a floor drain opening, a sewage discharging opening of a wash basin and a sewage discharging opening of a washing machine on the integral bathroom chassis is guided to the side surface of the chassis and collected and discharged from the same drain pipe, meanwhile, the problems of layer height and waterproof reliability are solved, and the great advanced application in an LOFT architecture is achieved.