A stud pin for mounting in a pneumatic tire includes a tip including a tip end surface configured to come into contact with a road surface, and a body portion configured to house the tip. An end surface of the tip configured to come into contact with a road surface comprises an axis of symmetry which defines a line symmetrical shape of the end surface; a centroid of a shape of the end surface offset to a first side in an axial direction from a center position of a range the end surface covers in the axial direction of the axis of symmetry; and a recessed portion recessed inward of the end surface, the recessed portion being provided on, of peripheries of the end surface, a periphery of the end surface running between a first most distal end portion and a second most distal end portion.