To obtain a cast product which is easily taken out from a cast mold, has the whole length having longer than metallic fuel length regulated in manufacturing specifications and is free from rough surface.

In the tubular mold casting for metal injection molding, having a coating layer for releasing from the mold and/or preventing the reaction on the inner surface of the tube, a gas exhaust hole for exhausting the gas from the inner part of the tube, is provided at a position defining the upper part when the casting is performed.