A casting nozzle suited to manufacture a casting material of pure magnesium or magnesium alloy is provided. A nozzle 1 is utilized to manufacture a casting material 100 by supplying molten metal to a portion between rolls 10 which become a casting die, and arranged so that a pouring port 4 is located between a pair of rolls 10 opposed to other. This nozzle 1 includes a main body 1a formed of oxide material such as alumina, and a coating layer 3 which is provided on the inner surface of the main body 1a which comes into contact the molten metal, and formed of material that does not include oxygen substantially. Since the main body 1a does not come into direct contact with the molten metal due to the coating layer 3, it is possible to prevent oxygen included in the main body 1a from reacting with the molten metal. Further, in the nozzle 1, a casting die contact portion 2 which comes into contact with the rollers 10 is formed of thermal insulation material, whereby it is prevented that the molten metal in the nozzle 1 is cooled through the casting die contact portion 2 by the rollers 10.