The invention provides a single-phase five-level topology and an inverter. The single-phase five-level topology comprises a first capacitor, a three-level bridge arm module and four switching tubes, wherein the four switching tubes refer to a first switching tube, a fifth switching tube, a sixth switching tube and an eighth switching tube respectively; each switching tube is reversely connected in parallel with a diode; the three-level bridge arm module comprises two switching tubes and a double-switch unit; the first end of a third switching tube is connected with a first node, and the second end of the third switching tube is connected with a neutral point N through the double-switch unit; and the first end of a fourth switching tube is connected with N through the double-switch unit, and the second end of the fourth switching tube is connected with a second node. Five level states are output, the current harmonic content of a system is reduced, the filter inductance is reduced, the voltage level is raised, the common-mode voltage is restrained, and the running efficiency is increased. Balanced control of capacitor voltage under full power and full modulation can be realized without adding an additional hardware circuit, and the phase output voltage of the system is prevented from degrading from five levels to three levels.