The present invention provides an artificial joint stem, an artificial joint stem component, and an artificial joint stem manufacturing method with which the amount of labor required in manufacturing is reduced, the strength can be increased through the suppression of stress concentration, and the degree of freedom in the shape is high. A stem includes a stem body portion and a porous portion that has a porous body and is bonded to the stem body portion. The stem body portion has an insertion portion arranged to be inserted into a medullary cavity of a femur. The porous portion is a tubular standalone portion formed by stacking layers of a biocompatible metal powder, and is arranged so as to surround a proximal portion of the insertion portion.