Abstract: An assembling apparatus which can readily achieve change-over among operation programs corresponding to a large number of works of different models. Part pallets on which parts are received are supplied from a part supplying unit to a plurality of assembling units by a part pallet supplying conveyor. Meanwhile, assembling pallets are supplied from a model changing unit to the assembling units by an assembling pallet transporting conveyor. Each of the assembling units is provided with an orthogonal robot wherein an assembling head picks up a part from a part pallet supplied thereto and automatically mounts the part to a work on an assembling pallet supplied thereto.