To provide a method and an apparatus for manufacturing an optical device, which enable smooth position adjustment of an optical modulator even in the case that a head body shape is made complicated in order to cope with a high luminance and a high performance of a projector.

The apparatus for manufacturing an optical device 140 is provided with a 6-shaft position adjustment unit 31 for position adjustment of an optical modulator 141, a support jig 33 for placing and fixing the optical device 140, and a luminous flux detector 40, and the support jig 33 has a support piece 336 for supporting the weight of a panel unit 190 (the optical modulator 141). While the optical device 140 is installed on the support jig 33, the support piece 336 is arranged so as to face an opening part 151C formed in a head body 150 and is moved to project and retreat through the opening part 151C.