Considering the high probability of the participation of stray dogs in the reservation and transmission of pathogens of infectious and invasive etiology, strict control is necessary not only over specific prevention, but also over the diagnosis of these diseases. Fleas are the most common ectoparasites in domestic animals. Flea parasitism in dogs is accompanied by anxiety, itching, and an allergic reaction. In addition, fleas are intermediate hosts of the causative agent of dipylidia. The purpose of the research was to study the spread of ctenocephalidosis among stray dogs in the city of Tyumen. The work was completed between 2016 and 2020. On the basis of the temporary detention center for stray pets of the Municipal government institution "LesParkKhoz" in Tyumen. A total of 4817 stray dogs were examined. For diagnosis, clinical, epizootological and parasitological research methods were used, the results obtained were processed using statistical methods. It was found that ctenocephalidosis occurred in 22.30% of stray dogs in the city of Tyumen. Most often, ctenocephalidosis was recorded among stray puppies under 1 year of age (36.03%) and in stray dogs aged 3 to 6 years (32.97%). Ctenocephalidosis was diagnosed throughout the year, the peak incidence was recorded in the autumn period in 46.28% of cases (of all cases of ctenocephalidosis for the specified period). Almost at the same level, flea infestation was recorded in spring and summer at 20.95% and 24.11%, respectively. Most often, stray dogs with ctenocephalidosis were admitted to the municipal shelter from the Central Administrative District (EI - 65.41% with AI 10.1 ± 0.5 individuals/animal). The causative agents of ctenocephalidosis in stray dogs in the city of Tyumen are C. felis and C. canis with a dominance index of 84.96% and 15.04%, respectively.