A method of manufacturing semi-solidified molten metal includes a step of keeping discharging inert gas from a probe in a continuous manner, and inserting the probe into molten metal held at a temperature that is higher than a temperature of the probe and that is equal to or higher than a liquidus-line temperature, a step of extracting the inserted probe from the molten metal such that at least part of a region of a surface of the inserted probe that is in contact with the molten metal is exposed from the molten metal, and a step of inserting the extracted probe again into the molten metal.