To facilitate handing of a culture vessel by an automatic machine such as a robot, etc., and to more surely and prevent the culture vessel from falling by a simple and inexpensive method.

The adapter 1 for the culture vessel is detachably attached to the outside of the culture vessel 6 for storing a medium A to which a specimen is supplied. The adapter 1 for the culture vessel is equipped with a vessel placing part 3 for placing the culture vessel 6 and a projection part 4 which is arranged so as to extend from the side of the culture vessel 6 outwards when the culture vessel 6 is placed on the vessel placing part 3.