The invention discloses a vibration-absorption mechanism of a tractor. The vibration-absorption mechanism comprises a tractor body, a first fixing plate, a shock-absorption device, a second fixing plate, supporting rods and a plurality of tires. One supporting rod is arranged between every two adjacent tires, the second fixing plate is arranged on the tops of the supporting rods, the vibration-absorption device is arranged on the top of the second fixing plate, and the first fixing plate is arranged between the top of the vibration-absorption device and the tractor body, wherein the vibration-absorption device comprises a sucker rod, and the two ends of the sucker rod penetrate through the first fixing plate and the second fixing plate respectively. A supporting structure is inserted intothe lower portion of the sucker rod in a penetrating mode, and the supporting structure is composed of a bottom plate, an arc plate and a plurality of supporting columns, wherein the supporting columns are arranged on the two sides on the top of the bottom plate respectively, the arc plate is transversely arranged between the tops of the supporting columns in a penetrating mode. The vibration-absorption mechanism has the advantages that the tractor body is effectively protected, the vibration generated in the work of the tractor is reduced, and the service life of the tractor is prolonged.