To provide a frequency converter that can stably be operated without intermitting the current even under a lightly loaded condition.

The output side of the first converter composed of a forward conversion part 1-1, a DC reactor 2-1 and a reverse conversion part 3-1, and the output side of the second converter composed of a forward conversion part 3-1, a DC reactor 2-2 and a reverse conversion part 3-2 are connected in the vicinity of a connecting point of a capacitor 4b of a load 4. Only one of the two converters is operated until an output current of the frequency converter exceeds a prescribed value, and the other makes the reverse conversion part on standby in a bypass pair state. When the output current exceeds the prescribed value, both the tow converters are parallel-operated, thereby allowing the converter to be operated without intermitting the current even under the light load condition.