An inventory of upper subtidal Cystoseira (0-5 m depth) of the Tunisian coasts (La Galite Archipelago excluded) was carried out from March 2012 to February 2013. Seven Mediterranean endemic taxa new for Tunisia were collected: 4 species, Cystoseira algeriensis, C. barbatula, C. crinitophylla, C. susanensis, and 3 infraspecific taxa, C. compressa f. plana, C. foeniculacea f. latiramosa and f. tenuiramosa. Each taxon is described and their Tunisian range of distribution is given and discussed.