See text Butomus is the only known genus in the plant family Butomaceae, native to Europe and Asia.

It is considered invasive in some parts of the United States.

The APG II system, of 2003 (unchanged from the APG system, 1998), also recognizes such a family, and places it in the order Alismatales, in the clade monocots.

At the ranks of family and order, this is the same placement as in the Cronquist system.

The family counts one species, Butomus umbellatus, or two according to some authorities.