There is provided a plant-transplanting device that, with a simple structure and at a low cost, realizes speedy and stable transplantation, prevents damage to a plant, and is easily automated. A plant-transplanting device 100 that transplants a seedbed B from a plant holder 110 to a cultivation pallet 120 includes a holder retaining mechanism 130, a pallet retaining mechanism 140 for retaining the cultivation pallet 120 below a holder retaining position of the holder retaining mechanism 130, and a lowering mechanism 150 for lowering the seedbed B retained by a holder seedbed retaining part 111 downward and inserting the seedbed B into a pallet seedbed retaining part 121.
