To provide stacking device for raising seedling box with enhanced processing potential of total device by quickly carrying out a group of raising seedling boxes which are stacked highly.

The stacking device for raising seedling box comprises a raising seedling box stacking mechanism 1 which brings up conveyed raising seedling boxes w and sequentially stacks up from bottom, a conveying and loading mechanism 2 which brings together the groups w of raising seedling boxes stacked up in a predetermined numbers and conveys onto a taking/transporting mechanism 3 waiting at a predetermined seedling box loading position, wherein the taking/transporting mechanism 3 is provided with a fork-like transport/load supporting arm 73, a driving means moving the transport/load supporting arm 73 to-and-fro along the longitudinal direction of the arm and a driving means vertically and parallelly moving the transport/load supporting arm 73, and the groups W of the raising seedling boxes loaded/held on the taking/transporting mechanism 3 are set to transfer and to be loaded on a conveying carrier D waiting on a predetermined position by the parallel lifting and movement of the transport/load supporting arm 73.