For the existing two kinds of composite energy storage hybrid system based on accumulators and ultra capacitor,which kind of composite energy storage type’s fuel economy is higher remains to be studied.Loader,for example,the structure characteristics of the two kinds of composite energy storage hybrid loader which were composed of energy storage device were analyzed.From the perspective of energy flow,the utilization of regenerative braking energy was calculated.Simulink models of the two hybrid system established under MATLAB were analyzed in four kinds of typical operation modes.The simulation results show that the composite energy storage type hybrid loader based on the accumulator has better fuel economy under the four kinds of typical working environment.The comparison will provide a basis for the design and application of the two composite energy storage hybrid systems.