In biology, a subgenus is a taxonomic grade intermediate between genus and species.

The subgeneric name is generally shown in brackets, placed between the genus and species name. It can even be the same as the generic name. e.g. the Tiger Cowry of the Indo-Pacific, Cypraea (Cypraea) tigris Linnaeus belongs to the subgenus Cypraea of the genus Cypraea.

Unlike the generic and specific names, it is not mandatory, when describing a species, to include the subgeneric name.

Note also that a name included in brackets is also sometimes used to indicate differences of taxonomic opinion, e.g. the Northern Gannet: Sula (Morus) bassana means that some people treat the species in the genus Sula, while others split it off into a separate genus Morus.