High pressure casting sand core and method of manufacturing the same

A sand core adapted for high pressure casting is formed by a core body and a support pin to be connected to the core body. The support pin is provided with one end portion to be embedded in said core body and the other end portion projected outwardly from the core body. A connecting means is formed to the embedded portion so as to integrally connect the core body and the support pin and a support pin positioning and supporting means is formed at the projecting portion of the support pin. Positioning pins extending from a core formation mold are engaged with the positioning and supporting means so that the embedded end portion of the support pin is positioned in the cavity of the core formation mold. The cavity is filled with core sand whereby the embedded one end of the support pin is supported to integrally form the support pin and the core body. The sand core is dipped in a slurry including a sand core coating material and then heated and dried.