Provided are: a container connector that can be connected to containers having differing outside diameters and that can be connected to containers in a simple manner, the container connector making it possible to stabilize the orientation of a connection state; and a connection device having the container connector. This container connector 10 comprises: a base part 20 in which an L is formed; three or more joining parts 30 disposed on a circle X that is set for the base part 20; a guide part 41 provided so as to be continuous with the joining parts 30, the guide part 41 being capable of guiding a container 5 to the joining parts 30, and having an inner surface 41 formed in an inclined plane that is inclined relative to the axis C3 of the circle X or a curved surface; and an arm part 60 provided to the base part 20, the arm part 60 supporting the guide part 40 so as to be capable of swinging in a direction toward the axis C3 of the circle X and a direction away from the axis C3.