The invention relates to an integrated intelligent monitoring and controlling system and method of a safety mechanism screw thread pair gap of a ship lift. The system comprises a light source cooperating with a remotely controlled camera to carrying out shooting on a position of cooperation of a locking screw rod and a nut post of a ship lift. The remotely controlled camera is installed at a remotely controlled cloud desk. The light source and the remotely controlled cloud desk are fixed at a mounting bracket fixedly installed at the position of cooperation of the locking screw rod and the nut post of the ship lift. The remotely controlled cloud desk and the remotely controlled camera are connected with a control box. A microprocessor, a controller and a touch screen are installed inside the control box; a data input terminal of the microprocessor is connected with the remotely controlled camera by a special cable and the microprocessor can receive and process a screw thread pair gap image obtained by a zoom lens; and a data output terminal of the microprocessor is connected with the controller. The controller is connected with a ship lift control system and controls an execution mechanism to make action.