The invention discloses a power generation energy storage device based on cascade H bridge and multiport DC converter. The power generation energy storage device comprises a first full-bridge converter connected with a power generation module, a second full-bridge converter connected with an energy storage module, a third full-bridge converter connected with a multi-winding transformer, and a H bridge converter connected with an electric grid through a filter inductor. By a power generation / energy storage hybrid device, irregular new energy generated power becomes relatively smooth, and an electric grid current is limited when electric grid voltage drops. A multiport full-bridge isolated DC / DC converter can realize flexible match between the power generation module and the energy storage module with different output voltage grades, meanwhile, soft switching is realized by transformer leakage inductance and switching element stray capacitance, relatively high efficiency and electric isolation are realized, and cost is lowered. The cascade H bridge inverter is used on the electric grid side, thus, multi-level output voltage is obtained, and electromagnetic compatibility and grid connection harmonic performance are improved.