The invention discloses a high-frequency isolation five-level inverter, which is composed of an input direct current power supply, voltage dividing capacitors, a high-frequency isolation five-level conversion unit, an output frequency converter, an output filter and an output alternating current load connected in sequence; according to the inverter, based on the full-bridge inverter, the voltage is divided by connecting two capacitors at two ends of the input direct current voltage source in parallel, thus the front end of the transformer can generate five levels including Udc, Udc/2, 0, -U/dc/2 and -Udc, and the five levels can be simultaneously inducted at a transformation secondary, the voltage stress of a switch tube is reduced, and meanwhile, the waveform quality of output voltages is improved. The inverter has the advantages of two-stage power conversion (DC-HFAC-LFAC), bidirectional power flow, low switch device voltage stress, good frequency spectrum characteristic of front-end voltage of output filter, small size of output filter, and high-frequency electrical isolation of AC load and DC power supply. The inverter is low in switch tube voltage stress, and can be applied to the application fields with higher voltage and large power.