which is separately manufactured by diffusion bonding further as another convenient method a ring of an alloy steel may be installed at this portion as another preferable injection sleeve for die casting of this invention a tapered portion is provided on the outer periphery of the cylindrical cermet sintered body of the injection sleeve in the vicinity of an end portion contacting the die casting mold which fits to a tapered portion provided on an inner periphery of a corresponding end portion of a fitted metal cylinder and the other end portion of the cylindrical cermet sintered body is fixed such that the cylindrical cermet sintered body does not come off by a metal ring which is installed to the other end portion of the metal cylinder all the inner face of the injection sleeve up to the portion contacting the die casting mold can be constructed by the cermet sintered body since the portion of the cylindrical cermet sintered body in the vicinity contacting the die casting mold has the tapered portion thereby the excellent service life of the injection sleeve can be provided further when the shrinkage fit is performed by a metal cylinder having a larger thermal expansion and smaller young 39 s modulus than those of the cermet sintered body the cylindrical cermet sintered body may partially be protruded by the residual stress accompanied by the shrinkage fit therefore there may be a case wherein the cylindrical cermet sintered body comes off the injection sleeve and the edge of the cylindrical cermet sintered body is tipped off however the injection sleeve is provided with the metal ring on the side of.