The present study provides new information about the diversity of freshwater and terrestrial cyanoprokaryotes of the western part of the Oscar II Land, Spitsbergen (Svalbard) archipelago. Altogether, and 51 taxa were found in different habitats (29 species was found on wet rocks, 21 on the seepages, 18 on the lakes, 11 on the moss tundra), mainly in wet ones. Nostoc commune, Gloeocapsa kuetzingiana, Microcoleus autumnalis, and Microcoleus vaginatus dominated almost all types of habitats. Aphanocapsa rivularis and Woronichinia karelica are reported for the first time for Spitsbergen flora. The studied flora is most similar to the flora of the vicinity of settlement Pyramiden. Since all these areas are dominated by carbonate rocks, it can assume that this might be due to the similarity of the geological conditions. In general, the cyanobacterial (cyanoprokaryotes) flora of western part of the Oscar II Land includes widespread, frequent and typical Spitsbergen species
