Review of theriological studies carried out after the accident at the Chornobyl NPP, in the exclusion zone (2600 km2 of mainly woodlands in the north of Kyiv Oblast, which were affected in the result of radiation contamination and excluded from economic use). It is noted that before the accident (1986) the regional theriofauna was poorly known while over the next 40 years it became one of the most well studied in Ukraine. Theriological knowledge assisted to justify the necessity to save the Chornobyl nature and to create the Chornobyl Biosphere Reserve. In contrast to the first decade, when assessments of the radiation impact on the fauna predominated, investigations of the last 20 years have paid more attention to issues of species diversity, spatial distribution, population dynamics, interspecific relationships, and species conservation activity.