A high-voltage-gain five-level inverter topological circuit. A single-phase five-level inverter topological circuit comprises a half-bridge inverter circuit, and the half-bridge inverter circuit comprises a flying capacitor (Cs) and outputs five different levels comprising a zero level. The single-phase five-level inverter topological circuit adopts a five-level half-bridge structure, and only needs one alternating-current filter inductor (L1), thereby reducing the cost and the volume of a system, completely removing leak current, and having high efficiency and high stability. Under the same running condition, the voltage utilization rate of the high-voltage-gain five-level inverter topological circuit is twice of that of an existing half-bridge five-level inverter topological circuit; and neutral-point voltage at the direct current side can be automatically balanced without an additional circuit.