The present invention discloses a single-phase and three-phase dual-purpose two-level low-frequency power circuit. The circuit comprises a transformer, a first rectifier, a second rectifier, a first single-phase inverter having a first bridge arm and a second bridge arm, and a second single-phase inverter having a third bridge arm and a fourth bridge arm; the input end of the transformer is connected with a power source, the first output end of the transformer is cascaded with the first rectifier and the first single-phase inverter in order, and the second output end of the transformer is cascaded with the second rectifier and the second single-phase inverter in order; the single-phase and three-phase dual-purpose two-level low-frequency power circuit also comprises a first switch and a second switch, the first bridge arm and the second bridge arm form the first single-phase inverter, or the second bridge arm and the second single-phase inverter form a three-phase inverter by operablyclosing or disconnecting the electrical connection of the first bridge arm and the second bridge arm at the same time; and the second single-phase inverter and the three-phase inverter are two-level inverters. The single-phase and three-phase dual-purpose two-level low-frequency power circuit can achieve single-phase output and three-phase output to be used for field drying of a large-scale powertransformer.