The area of Odonata exploration belongs to the Orava region, which is situated in NW Slovakia. The examined localities spread out in the lower part of inundation area of the Orava river, in surroundings of the town Dolný Kubín. The entire research of dragonflies was carried out in years 2008 – 2010 at 6 localities, which represent 6 types of biotopes – a gravel pit, an oxbow lake, an old river branch, a submontane river, an oxbow-lake and old flooded quarries and gravel-pit. 29 species of dragonflies have been found in the localities. The eudominant ones are Coenagrion puella (Linnaeus, 1758), Enallagma cyathigerum (Charpentier, 1840), Platycnemis pennipes (Pallas, 1771) and Erythromma najas (Hansemann, 1823) respectively. There are 10 endangered species e. g. Sympecma fusca (Vander Linden, 1820), Somatochlora meridionalis (Nielsen, 1935), Crocothemis erythraea (Brullé, 1832) and Sympetrum meridionale (Selys, 1841). From the Odonata biodiversity point of view the most valuable locality is the above mentioned gravel-pit Párnica. We have found 23 Odonata species there.