To provide a microwave melting system and a microwave melting method capable of simply extinguishing plasma produced by irradiation of microwaves.

A microwave melting system comprises a circular waveguide 8, a chamber 11, a power supply 12, a small power pulsed waveform generator 13, and a microwave oscillation apparatus 14 such as a gyrotron and a magnetron, for pulsed irradiation of microwaves. In order to extinguish the plasma produced by the irradiation of the microwaves during the irradiation time interval in the pulsed irradiation, no radiation or low energy irradiation is performed in the irradiation suppress time interval. In a microwave melting method pulsed microwaves are irradiated such that the irradiation suppress time interval is at least 50 msec, and such that a duty ratio in one period is at least 90%.