To safely sterilize medical waste by burning gas in a melting furnace and a charging chamber introduced by a gas introducing part, together with fuel.

This melting apparatus includes the melting furnace 100 holding the medical waste 20; a heating section 140 burning fuel to heat the inside of the melting furnace 100 to a sterilizing temperature higher than temperature at which at least part of the medical waste 20 melts and lower than the thermo-decomposition temperature of the medical waste 20; the charging chamber 170 that can be connected to and shut off from the melting furnace 100 and the outside, holds the medical waste 20 charged from the outside when connected to the outside during heating of the melting furnace 100, and charges the medical waste 20 into the melting furnace 100 when connected to the melting furnace; and the gas introducing part 180 taking in gas 42 in the melting furnace 100 during heating to introduce the gas into the heating section 140. The gas introducing part 180 takes in the gas 44 in the charging chamber during heating to introduce the gas into the heating section 140, and the heating section 140 burns the gas in the melting furnace 100 and the charging chamber 170 introduced by the gas introducing part 180, together with the fuel.