The invention discloses a testing system of a pilot-operated type load control valve. The testing system of the pilot-operated type load control valve comprises a main oil line hydraulic pump, a pilot-operated oil line hydraulic pump, a proportional overflow valve, a manual overflow valve, a pilot-operated two-way cartridge valve, a main oil line pilot-operated reversing valve, a proportional pressure reducing valve, a leading oil line pilot-operated reversing valve, a manual directional valve, a tested load control valve, a loading pressure transmitter, an oil return pressure transmitter, a control pressure transmitter, a flowmeter, a power amplification device, a data acquisition card, a computer, a main phase step module and a pilot-operated phase step module. The testing system of the pilot-operated type load control valve can conduct comprehensive testing on the one-way connecting characteristic, the load pressure - flow characteristic, the control pressure - flow characteristic, the load pressure phase step characteristic and the control pressure phase step characteristic of the pilot-operated type load control valve.