The hepatitis E virus (HEV) is the cause of hepatitis E in humans around the world. Due to the exposure of a large part of the population and consequently a significant number of infected infections, HEV is one of the most significant threats to public health globally. The hepatitis E virus is divided into eight genotypes of which the HEV GT-3 and HEV GT-4 genotypes have zoonotic properties and can be spread from animals to humans. So far, it has been proven that domestic pigs, wild boar and deer are the most important species for the transmission of HEV to humans. Exposure to HEV has been confirmed in some other species, but research on HEV infections in horses and pets, animal species in close coexistence and contact with humans, is still very rare, and has never been conducted in the Republic of Croatia. The aim of this study was to examine for the first time the presence and prevalence of hepatitis E virus infection in horses and domestic carnivores. A total of 264 horse serum samples, 308 dog serum samples and 88 cat serum samples were examined using a commercial ELISA (ID Screen Hepatitis E Indirect Multi-species test). Out of a total of 660 examined animals, all three studied species from the territory of the Republic of Croatia, HEV infection was confirmed in one dog (0.15%). This data proves that horses and pets are currently not a significant factor in the spread of HEV, and that anti-epidemic measures in the epidemiological and epizootiological situation of the Republic of Croatia must primarily focus on breeding domestic pigs, prevent infection during contact with feral pigs and general food safety. However, due to the first confirmed HEV infection in the territory of the Republic of Croatia, proven by this research, it is certainly justified to conduct further research in the searched species in order to collect additional epizootiological and epidemiological knowledge. Moreover, since a serologically positive dog showed clinical signs of acute gastroenteritis and liver dysfunction, research should be continued to clarify the significance of hepatitis E virus infection in dogs in veterinary clinical practice.