Polygala turcica Donmez & Ugurlu (Polygalaceae) is described and illustrated as a new species from Kars province in E Turkey. It is similar to P. peshmenii Eren & al., but is clearly isolated from the other species of Polygala sect. Polygala with respect to habit and morphological characters. Morphology, including that of pollen, is discussed with respect to taxonomic value. The conservation status of the new species is assessed. A new identification key is provided for all Polygala species known from Turkey.