Starting apparatus for internal combustion engine

A starting apparatus (1) includes a starter motor (2) and a gear train (4) that transmits the rotation of the starter motor (2) to a crankshaft (3) of the engine; the gear train (4) includes a starter gear (5), a driven gear (6) that is meshed with the starter gear (5), and an intermediate gear (7) provided on the same axis as the driven gear (6); the driven gear (6) includes a tooth portion (6a) constructed of helical teeth and a driven gear shaft (6b) which is supported so as to be able to move along a rotational axis (CL); the intermediate gear (7) includes an intermediate gear shaft (7b); and a pair of threaded portions (15, 16) serving as auxiliary rotation transmitting means is provided, one on a rotation transmitting portion (6c) of the driven gear shaft (6b) and the other at a corresponding position on the intermediate gear shaft (7b) of the intermediate gear (7), which faces the one on the rotation transmitting portion (6c).