The invention relates to a single counterweight type automatic
levelling spreader and a using method thereof, belonging to the technique of loading-unloading winching device. The single counterweight type automatic
levelling spreader comprises a bearing spreader, an automatic
levelling device, an initial bottom
surface distance measurer, a target bottom
surface distance measurer and a computer, wherein the automatic levelling device is mounted on the bearing spreader and is provided with counterweight blocks; the initial bottom
surface distance measurer and the target bottom surface distance measurer are respectively located below an initial bearing bracket and a target bearing bracket; the computer communicates with both the bottom distance measurers, calculates the leveling inclination angle of the loading
butt joint surface according to information measured by the initial bottom surface distance measurer and the target bottom surface distance measurer and based on the input structural size of the loading
butt joint surface, calculates control signals, transmits the control signals to the automatic levelling device, controls the position of the counterweight block in the automatic levelling device and keeps the initial bearing bracket and horizontal target bearing bracket of the loading
butt joint in the horizontal state so as to realize precise and easily damaged hoisting. The invention has the advantages of high precision,
fast speed, safety and reliability.