Nebularia is a genus of predatory sea snails, marine gastropod mollusks in the subfamily Cylindromitrinae within the family of Mitridae.

[1] This name was originally proposed as a subgenus of the genus Mitra.

The type species of this genus is Mitra contracta Swainson, 1820.

In 1991, Cernohorsky considered that the subgenus Nebularia does not form a well-defined group.

[2] In 2001, Thorsson and Salisbury used the tern Nebularia as a group (and not as a valid taxonomic name), for species related to the type species Mitra coronata.