An energy management strategy for an electricity-hydrogen coupled DC microgrid based on cascade fuzzy control is proposed to address the power allocation problem faced by an electricity-hydrogen hybrid energy storage system when smoothing out power fluctuations in a DC microgrid. In this strategy, the primary fuzzy controller works out the primary power allocation factor based on the state of hydrogen storage (SOH) of the hydrogen storage tank and the state of charge (SOC) of the lithium-ion battery and performs primary allocation of the DC microgrid net power. The secondary fuzzy controller combines the reference value of primary power allocation and the SOH to correct the primary power allocation factor. In addition, to enable current-controlled devices (electrolysers and fuel cells) with nonlinear operating characteristics to respond efficiently to the energy management system, an interpolation method is used to convert the power distribution reference value to a current reference value. Matlab/Simulink simulation results prove that the strategy effectively narrows the power fluctuation range in the unreasonable range and improves the accuracy and speed of the device response in the system.