To provide a gas dissolved washing water supply apparatus with enables successively supplying plural kinds of gas dissolved washing water by using a simple apparatus of one series and corresponding to a one-bath type washer or a leaf type washer.

This gas dissolving washing water supply apparatus is provided with a gas dissolving part which is composed of one of plural gas dissolvers 1 of mixing type which directly mixes gas and pure water and dissolves the gas, a pure water supply piping 2 which supplies pure water to the gas dissolving part, a gas supply means which supplies plural kinds of gas to the gas dissolving part, a supplying pipe 6 which sends out the gas dissolved washing water into the gas dissolving part and a gas-liquid separator 7 which is disposed on the supplying pipe.