Metridiidae is a family of sea anemones in the order Actiniaria.

[2] Members of the family Metridiidae are characterised by having a mesogloeal sphincter muscle and by the mesenterial arrangement, with the mesenteries not being divided into macronemes and microcnemes.

The acontia typically have microbasic b-mastigophors and microbasic amastigophors, though the latter are not always present in adults.

[1] The following genera are recognised by the World Register of Marine Species (WoRMS):[3] Of these, Metridium is the most speciose while Paraisometridium is monotypic.

This Actiniaria-related article is a stub.