An excavator energy-recuperation system relates to an excavator moving arm energy saving system, comprising a hydraulic cylinder, a fuel tank, a quantitative pump, a valve and an engine. The key technology is that a first variable pump and a speed determining photoelectric encoder are coaxial equipped with the quantitative pump. One end of the quantitative pump is connected with a hydraulic cylinder through a reversing valve and the other end of the quantitative pump is respectively connected with the fuel tank and the hydraulic cylinder on two branches. One end of the first variable pump is connected with the fuel tank and the other end is connected with an accumulator through the reversing valve. A second variable pump is coaxial arranged with the engine, one end of the second variable pump is connected with the fuel tank and and the other end is connected with a check valve; a fuel outlet of the check valve has three branches, wherein the first one is connected with the accumulatorthrough the reversing valve; the second one is connected with a hydraulic cylinder through the reversing valve; and the third one is connected with a hydraulic cylinder through the reversing valve. The invention combines the flow regeneration and potential energy recuperation, thus simultaneously realizing the flow regeneration and the energy-recuperation recycling, improving the utilization rateof the excavator energy and prolonging the service life of the excavator.