The textbook consists of materials of lectures and practical classes. Lectures discusses the following topics: "Water pet", "Factors affecting the life of aquatic animals in the pond", "Achievements of ihtiopatologice to combat aquatic animal diseases", "Locasale parasites in the body of aquatic animals", "the Influence of parasites on host organism", "Contamination of aquatic animals depending on species", "Contamination of aquatic animals depending on age," "Contamination of aquatic animals with parasites, depending on the season of the year, Influence of acclimatization on contagiousness of aquatic animals", "Diagnosis of parasites of aquatic animals», "The basic principles of measures for the elimination of parasites of aquatic animals", "Basic epidemiology", "Review of measures on struggle against especially dangerous diseases of aquatic animals", "supervise the transport of aquatic animals intended for breeding and acclimatisation", "Disinfection and designwise ponds, hydraulic structures and equipment". The practical training includes six sections: "Diseases of fish", "Diseases of frogs", "Diseases of turtles", "Diseases of snakes", "Diseases of aquatic and near-water birds", "Diseases of aquatic mammals". The textbook describes infectious and invasive diseases of aquatic animals. The description of individual diseases provides information about the morphology and biology of pathogens, pathogenesis, clinical signs, pathological changes, diagnosis, as well as measures to combat a particular disease. Intended for doctoral students of specialty "Hunting study and fur farming", "Fishery and industrial fishing", "Veterinary medicine", "Veterinary sanitation", "Water resources and water use", veterinary doctors, ihtiopatologice, fish farmers. Keywords: aquatic animals, fish, frog, turtle, snake, water bird, wading birds, aquatic mammals, ecology, fish diseases, biotechnology, virosis, bacterioses, mycoses, parasitos, protozoan, ciliate, monogenoidea, trematoda, cestodes, nematodes, bellos, disease of frogs, diseases of turtles, diseases of snakes, disease of water birds, diseases of waterfowl, diseases of aquatic mammals.