The invention discloses a pressurized mopping robot and a working method thereof, and belongs to the technical field of intelligent robots. A robot body comprises a main body, a walking mechanism, a lifting plate and a dragging plate. The main body is connected with the walking mechanism, a lifting plate motor and a worm and gear mechanism are arranged on the main body, the lifting plate motor isconnected with a worm of the worm and gear mechanism, a worm gear of the worm and gear mechanism is in threaded connection with a first lead screw, and the first lead screw penetrates through the mainbody and is fixedly connected with the lifting plate; a carriage motor is arranged on the lifting plate, the carriage motor is connected with the carriage through a transmission mechanism, and a spring device is arranged between the transmission mechanism and the carriage; the charging and cleaning device comprises a shell, a water tank and a cleaning basin, the shell is connected with the watertank, the water tank is connected with the cleaning basin, the cleaning basin is detachably fixed below the shell, and a sensing device and a charging device are arranged on the shell. Certain pressure can be applied to the ground during mopping, so that the mopping effect is improved.