The article presents the results of studying the course of some nematodoses in turtles and tortoises kept in terrariums. Helminth infections account for 35 % of all parasitic diseases of reptiles and are a significant danger, especially after wintering and for weakened individuals. The purpose of the work is to establish the helminth fauna of turtles and clinical testing of the topical application of an anthelmintic on a lipophilic basis. Research methods are coprological, statistical. The greatest extensiveness and intensity of invasion were found in nematodes Tachygonetria spp. Wedi, 1862 (family Oxyuridae) and Angusticaecum spp. Baylis, 1920 (family Ascaridae). Identified pathogens under the conditions of wintering in terrariums and after it are able to cause manifested forms of the disease in connection with the stress experienced by turtles. Invasion of Tachigonetria spp. manifested by gastrointestinal disorders: diarrhea, regurgitation of feed, weakness. Parasitism of Angusticaecum spp. characterized in addition to disorders of the digestive system by signs of respiratory pathology: shortness of breath of the expiratory type, secretion of serous and serous-purulent exudate, snoring, coughing. The highest intensity of invasion by both genera of nematodes was found in the spring, in the period after wintering, and the lowest – in the summer, in the season of the hottest weather. During a clinical trial of the use of various anthelmintics and different ways of administering the drug, it was established that Panacur orally and Profender topically have high intensive efficacy, however, 100 % extensive efficacy was not found in both drugs. Topical application of Profender on a lipophilic basis showed better results of intensity, especially against Angusticaecum spp., than enteral administration of Panacur. High, but incomplete intensity effectiveness of both drugs against Tachigonetria spp. is explained by the extraordinary spread of the causative agent's eggs in the environment, their pronounced resistance to extreme environmental conditions, commensalism of nematodes. Preparations on a lipophilic basis for parenteral (topical) use have prospects for use in reptile veterinary medicine.