The invention discloses an intelligent hydraulic steering system of a tractor. The system comprises a fuel tank, a steering hydraulic pump, a steering gear and a steering execution unit, wherein the fuel tank, the steering hydraulic pump, the steering gear and the steering execution unit are in connection through fuel pipes in sequence, a control system and a solenoid valve are arranged between the fuel tank and the steering execution unit, and the solenoid valve is controlled to be switched on or switched off by the control system, so that the function of automatic steering is achieved. By means of the technical scheme, the manual operation load is relieved, meanwhile routine steering work of the tractor is not influenced, normal production of agriculture is ensured, the production cost is saved, and the working efficiency is improved.