Using ISSR analyses genetic relationships were studied between the populations of the next species of angustifoliate fescue: F. macutrensis, F. rupicola, F. arietina, F. valesiaca, F. pallens, F. psammophila and F. brevipila. High level of ISSR loci polymorphism (average 92.9%) was shown. The species specific amplicon was revealed for F. valesiaca as well as the common fragment was identified for two related species--F. pallens and F. psammophila. On the basis of NJ analyses the differentiation of species was confirmed on such large aggregates as F. glauca agg. and F. valesiaca agg. More clear differentiation of the species was shown for F. glauca agg., while for F. valesiaca agg. we have not found any regularity of genetic relations among the species that represent this aggregate.