Paleozoological collections contain rich and diversified sets from different geological periods. The most valuable are collections of:
- specimens of Devonian fishes from the Świętokrzystkie Mountains;
- extremely well preserved, Jurassic, mostly ammonite fauna in spherosideritic concretions from Łuków;
- rich collections of invertebrate marine fauna e.g. Cretaceous brachiopods, echinoids and belemnites from south and central Poland, Tertiary molluscs, predominantly pelecypods and gastropods originating from outcrops in the south-east margin of the Świętokrzyskie Mountains as well as from outcrops in other parts of southern Poland, Podolia and Volhynia (currently in Ukraine);
- collection of Neogene bone breccias from Węże;
- fossil vertebrate collections of bone remains of Pleistocene mammals found in glacial deposits – e.g. numerous remains of mammoth, forest elephant, and rhinoceros.