A fabricating method of a semiconductor package structure is provided. A dielectric layer having a first surface and a second surface is provided. A patterned metal layer has been formed on the first surface of the dielectric layer. An opening going through the first and the second surfaces is formed. A carrier having a third surface and a fourth surface is formed at the second surface. A portion of the third surface is exposed by the opening of the dielectric layer. A semiconductor die having a joining surface and a side-surface is joined in the opening. At least a through hole going through the third and the fourth surfaces is formed. A metal layer having at least a heat conductive post extending from the fourth surface of the carrier to the through hole and disposed in the through hole and a containing cavity is formed on the fourth surface.