he article presents information about new finds of desmid Bambusina borreri (= B. brebissonii Kütz. ex Kütz.) in Ukraine and analysis of its distribution in the country. Peculiar features of the genus are cylindrical or barrel-shaped cells arranged in slightly twisted non-mucous filaments. Bambusina borreri is cosmopolitan with a disjunctive rangeж its distribution is limited by pH and trophic level of water bodies. Environmental selectivity determines its low frequency of occurrence. The species was included in the third edition of the Red Data Book of Ukraine. The authors first discovered B. borreri in the swamp protected by the Chornolisky Landscape Reserve of National Importance (Kirovohrad Region, Ukraine).In the Maliovanka Regional Landscape Park (Khmelnytsky Region, Ukraine) this species was confirmed to inhabit Rusalchyne Lake and first found in three more lakes. In all cases B. borreri occurred in typical habitats: oligotrophic reservoirs with low pH. A list of locations and a map of the distribution of B. borreri in Ukraine has been compiled. Among 22 localities cited for this species five sites are currently dissappeared. Most of the B. borreri localities are situated in the Pripyat-Desna Algofloristic Subprovince and only two belong to the Middle Dnieper and Carpathian-Danube algofloristic subprovinces; this is due to ecological preferences of the species. It is important to note that 10 of the 17 still existing habitats of B. borreri are located within the objects of the Nature Preservation Fund of Ukraine, which is an important aspect of its conservation.