To strengthen a flooring of a refractory material made metallic molten metal gutter having a metallic molten metal flow runner, an upper face of which is kept open.

This gutter 10 for a metallic molten metal is composed of a figurated refractory brick 12 which forms a base of the runner 11 and is juxtapositioned in an extending direction of a runner 11, and a main body 13 formed by a non-figurated refractory material which integrally covers and holds a side wall of the runner 11, a side wall and the base of the figurated refractory brick 12. This figurated refractory brick 12 is a refractory material having either one or both of alumina and magnesia, and carbon as its main components, and furthermore a reinforcement processing is applied such as a press processing, baking and the like. Therefore, it is hard to be impaired by the weight and the like of the metallic molten metal.