The presence of antibodies against Chlamydophila (Chlamydia) psittaci insmall mammals (Insectivora, Rodentia) in the region of East Slovakia are presented. The hosts were caughtin several areas of Slovakia in habitats with different levels of anthropogenic disturbance. Researchwas carried out during 2000-2002. The authors examined 1,947 sera coming from 4 insectivore and 10 rodentspecies. Each serum was examined by micromethod of complement binding reactions using antigen Chlamydophila(Chlamydia) psittaci. Chlamydial infections were found in 251 individuals (prevalence 12.9 %) of 8 mammalspecies. The antichlamydial antibodies were proved at levels ranging from 1:32-1:1024. The highest prevalenceof antibodies was detected in the most abundant rodent species Apodemus microps (14.8 %), Apodemus agrarius(13.9 %), Apodemus flavicolis (12.4 %), Microtus arvalis (12 %), and Clethrionomys glareolus (10.9 %).Positive hosts were registered in all studied localities. Testing of prevalence values in the individualresearch years confirmed significant changes. Our results showed that small mammals probably play animportant role in the circulation of chlamydiae in nature.