PURPOSE: To provide a molten metal pouring nozzle which is easily worked and difficult to break and has small pressure loss and is difficult to develop the nozzle clogging at a low cost.

CONSTITUTION: The molten metal pouring nozzle 6 having rectangular cross section of the inner wall surface, is composed of a curving part 8 having the constant rectangular cross section or the constant long side or major axis length of oval cross section toward the lower end part but contracting while facing to the rugged 2 curving surfaces having the constant curvature radii in the short side or minor axial direction, and continued to this part, a parallel nozzle part 9 having the constant rectangular cross sectional part or oval cross section. As the flow discharged from the molten metal pouring nozzle 6 is quickly diffused, by stirring the molten metal in a mold without unevenness, remelt of solidified shell can be prevented. The quality of a product is improved and also, the nozzle clogging is difficult because of the simple shape, and the crack caused by thermal stress can be prevented, and the service life of the nozzle can be prolonged.