Serological monitoring as a component of the epidemiological surveillance, serves as a method for asses sing the intensity of possible contacts of the population with the natural-focal disease pathogen. The aim of the study was to analyze possible contacts of the population with the causative agent of tularemia, based on the results of serological study of blood sera of the healthy population conducted in 2023 on the territories of Donetsk and Lugansk People’s Republics, Zaporozhe and Kherson Regions. Materials and methods. Applying IHR/IHIR serological methods, we have tested 829 blood sera obtained in 2023, from individuals living in areas at increased risk of aggravation of epidemiological situation on tularemia, who had not previously participated in specific prevention measures against tularemia. Results and discussion. Positive results on the presence of anti-tularemia antibodies in IHR/IHIR in the four studied territories ranged from 18.5 to 40.0 %. The analysis of questionnaires, that were filled out by donors has made it possible to determine the conditions of possible human contact with the pathogen in the foci of infection. According to the results of the study, the contacts of the population with the components of the natural tularemia focus in the surveyed territories can be assessed as intense, since the presence of specific antibodies to the causative agent of tularemia in donors of all the studied regions, on average, amounted to 24.4 %. Analysis of the data from the survey showed that all samples, in which antibodies to tularemia causative agent were detected, were registered from donors who may have had contact with carriers and vectors of the pathogen. According to the results of the study, small mammals contribute the most to the possible contact of the population with the causative agent of tularemia.