To provide a compact device for rearing aquatic organisms, enabling the aquatic organisms to be subdivided or enabling the organisms to be reared individually under good control, and further enabling rearing containers for storing the aquatic organisms to be inserted and removed individually.

The device for rearing the aquatic organisms comprises a holding body 1 and the rearing container 3 for storing the aquatic organisms. The holding body has an opened storing chamber 4 in which the rearing container is held so as to be freely inserted and removed. The device for rearing the aquatic organisms comprises a holding body 1 and a plurality of the rearing containers 3 for storing the aquatic organisms. The holding body has a plurality of the opened storing chambers 4 in which the rearing containers are held one by one so as to be freely inserted and removed.