Rabies is an especially dangerous anthropozoonosis caused by viruses of the Rabdoviridae family, genus Lyssavirus, known for over 4,000 years. There is no effective antiviral treatment for rabies, although immunobiological drugs have been developed, the timely application of which can prevent a fatal outcome in humans. Protection of the population from rabies includes control of zoonotic reservoirs and sources of the pathogen infection. The aim of the study was to assess the epizootic-epidemiological situation of rabies in Ukraine and Poland, considering risks caused by the active phase of the Russian-Ukrainian war. A comprehensive epidemiological method was used to analyze state official data regarding indicators of the epizootic process of rabies, the number and nature of human injuries due to animal attacks, and to determine trends during 2021–2023. A comparative-descriptive technique was applied to compare the effectiveness of vaccination against rabies in domestic, pet, and wild animals and to assess the risks of changes in the epizootic situation. Since the 1940s, a natural focal ecotype of rabies has formed in the Eastern European region, where wild carnivores are reservoirs and pathogen sources. In Ukraine, combined foci are registered with the natural focal ecotype of rabies, involving dogs, cats, and large and small ruminants in the epizootic process. The epizootic rabies situation in Ukraine worsened during the war due to the disruption of animal vaccination, increased feral domestic and farm animals, especially in the combat zone, and the cessation of regulating the normative number of red foxes. The epizootological well-being in Poland could be compromised if the rabies disaster area spreads from the border territories of Ukraine. There are real risks of worsening the epizootic-epidemiological situation of rabies in Ukraine, posing a threat of transboundary spread to other countries.