A high pressure injection nozzle member formed by liquid phase sintering without imparting external pressure and consisting of a hard material of carbide series mainly comprising a tungsten carbide, wherein the hard carbide material is composed of grains each having a diameter of less than 1 .mu.m, further comprising one, two or more kinds of carbides or carbon nitride, or solid solutions of carbides or nitrides selected from one of the group consisting of Ti, Ta, V, Cr, Nb, Mo, Hf, and Zr by a total weight % of 0.5 to 10% and a binding material essentially consisting of at least one kind of material selected from one of the group consisting Co, Ni, Fe, Au, Ag, Cu alloy, and Al alloy by weight % of 0.2 to 2.0%, said nozzle member being formed of a hard sintered material having a high abrasion proof property and having a hardness more than HRA 94.0.