Provided is a frequency converter for a frequency conversion microwave oven, comprising a rectification circuit, a switch circuit, a voltage inversion circuit, and a dual voltage output circuit which are sequentially connected, wherein the rectification circuit is connected with a commercial power voltage; the switch circuit is connected with a control center of the frequency conversion microwave oven; and the dual voltage output circuit is connected with a magnetron. The frequency converter further comprises a current detecting circuit, wherein the dual voltage output circuit is connected with the control center of the frequency conversion microwave oven via the current detecting circuit. The current detecting circuit comprises a current sampling resistor, with the current sampling resistor being serially connected between the dual voltage output circuit and the magnetron. The frequency converter of the frequency conversion microwave oven further comprises a voltage detecting circuit, with the dual voltage output circuit being connected with the control center of the frequency conversion microwave oven via the voltage detecting circuit. The frequency converter of the utility model features simple and reasonable structure, low making cost, high security degree, long service lifetime, and wide application range.