The invention discloses a hinged type gravity center adjusting device of a hillside tractor, and belongs to the technical field of agriculture mechanical equipment. The hinged type gravity center adjusting device of the hillside tractor comprises a left traveling mechanism, a right traveling mechanism, a left suspension frame hinged seat, a right suspension frame hinged seat, a suspension frame beam, a chassis, a suspension frame upright, a hydraulic cylinder, a hydraulic lock, a reversing valve, a hydraulic pump and an oil tank. An operator adjusts the relative positions of the left suspension frame hinged seat and the right suspension frame hinged seat and angles of the suspension fame beam and the horizontal direction by controlling the stroke of the hydraulic cylinder, and the vertical positions of the left traveling mechanism and the right traveling mechanism are adjusted, so that when the tractor travels on an inclined ground, the chassis remains level all the time. Good stability and safety of operation of the hillside tractor are guaranteed; the hinged type gravity center adjusting device of the hillside tractor is simple in structure, convenient to assemble, low in processing and manufacturing cost, good in universality of parts and easy to maintain and operate.