Harvester hydraulic system

The utility model discloses a hydraulic system of a harvester. The hydraulic system comprises a steering control unit and a working unit, the working unit comprises a working control valve and a working oil cylinder; the steering control unit comprises a main oil inlet, a diverter valve, a steering control valve, a steering oil cylinder, an unloading valve and an oil return port; the flow dividingvalve is provided with a flow inlet, a first flow dividing opening and a second flow dividing opening. Wherein the flow inlet is communicated with the main oil inlet, the first flow dividing openingis communicated with an inlet of the steering control valve, and the second flow dividing opening is respectively communicated with an inlet of the working control valve, an inlet of the unloading valve and an outlet of the steering control valve. The steering oil cylinder is controlled by a steering control valve, and the steering control valve is a three-position seven-way valve and is providedwith a left position, a mid