Cystoseira pustulata is a species of brown alga in the genus Cystoseira.

Cystoseira pustulata occurs in the Mediterranean and Northeast Atlantic (Azores, Canary Islands).

[2] Records of Cystoseira humilis in the Mediterranean refer to this species.

[2] Cystoseira pustulata has variously been treated as a variety or subspecies of Cystoseira compressa,[3][4][5] or considered a synonym of C. humilis,[6] but constitutes a distinct genetic entity not closely related to either.

[2]