The Nature Park Papuk is protected because of its extremely valuable biological, geological, landscape and historical features and includes almost the entire area of the Mountain Papuk and western part of the Mountain Krndija.
Almost 95% of the Park’s surface is covered with forests which are under special protection in some sites due to their scientific and landscape value.
From geological perspective, the Park is significant for its abundance of almost all types of rocks from Palaeozoic to Quaternary, as well as for the great diversity of rocks, minerals, fossils, geological structures and textures, karst phenomena and objects. The north-western part of the Park includes the site Rupnica – the first geological nature monument in Croatia – protected because of the step-like discharge of volcanic rocks and representing a unique geological phenomenon in our country. In 2007 this area became a Geopark due to its geological features. Because of its features, the Nature Park Papuk is a natural habitat to may animal species, among which birds and bats should be mentioned due to their number and diversity.