an apparatus for arraying parts on respective trays therefor comprises a tray - stocking device for receiving empty trays from a conveyor and maintaining a stock of the empty trays from which the latter are individually lifted by a first elevator to a conveying line extending above the tray - stocking device past a tray - accommodating station , a parts supplying mechanism disposed adjacent such station for selectively supplying parts to an empty tray disposed thereat , a vibrator for shaking the tray disposed at the tray - accommodating station and thereby arraying the parts supplied to the tray , whereupon the tray with parts arrayed thereon is withdrawn from the station along the conveying line , and a second elevator for removing the individual trays with parts arrayed thereon from the conveying line and for returning the removed trays with parts arrayed thereon to the first - mentioned conveyor .