Silene aydosensis K. Yildiz & S. Erik sp. nova (Caryophyllaceae, S. sect. Sclerocalycinae) is described and illustrated from S and SW Anatolia, Turkey. Diagnostic morphological characters for distinction from the similar S. caramanica and S. doganii are given. Distribution of the new and the morphologically similar species are mapped. Ultrastructure of seed and pollen grains of S. aydosensis was examined by SEM.