The paper presents the results of serological and bacteriological studies of materials from sheep for ovine infectious epididymitis of sheep, performed in state veterinary laboratories of the constituent entities of the Russian Federation in 2019. In total, during 2019, 384 735 serological studies of blood sera from rams and sheep were carried out in order to identify specific antibodies for infectious epididymitis in the reaction of long-term complement binding (RLCB). Positively reacting animals were found in 13 regions of the Russian Federation (0.04 %). The largest number of serological tests for infectious epididymitis was carried out in the Republic of Dagestan (56 387) and the largest number of positively reacting animals, was revealed (75), which amounted to 43.8 % of all positive cases in the Russian Federation. According to the results of complex bacteriological diagnostics of 216 aborted fetuses and 24 samples of pathological material from sheep for brucellosis, including ovine infectious epididymitis, performed in state veterinary laboratories of the constituent entities of the Russian Federation in 2019, the culture of the pathogen was not isolated. Conducting mass serological diagnostics of the disease in the reaction of long-term complement binding (RLCB) makes it possible to identify positively reacting animals and control the epizootic situation of ovine infectious epididymitis in the constituent entities of the Russian Federation.