To provide a raising-seedling pot refilling device enabling raising seedling pots to be refilled with raising seedling pots different in size, and reduced in introduction cost and maintenance cost.

The raising-seedling pot refilling device 100 is provided with a pot server unit 7 holding or detaching pots P to refill the pots P from a tray T to another tray T. The pot server unit 7 is necessary to be changed in its size in accordance with the size of each of the pots P and is structured so as to be flexibly attachable or detachable to or from the raising-seedling pot refilling device 100, so that another pot server unit 7 corresponding to the pots P different in size can be mounted. As a result of such a structure, only a single raising-seedling pot refilling device 100 responds to refilling of the refilling pots P different in size to reduce the introduction cost and maintenance cost of the raising seedling pot-refilling device 100.