The Royal Belgian Institute of Natural Sciences houses a precious collection of zoological, anthropological, paleontological, mineralogical and geological materials and data. The renowned Iguanodons from Bernissart, ambassadors of the Belgian science institute in Brussels, represent a natural history collection currently estimated to hold over 37 million specimens. The roots of the present day collection reach far back in history. It evolved from the Natural History collection of Karel of Lotharingen, governor of The Netherlands (1712-1780) and was part of didactic materials owned by the Central School of the City of Brussels. After the independence of Belgium, the City of Brussels donated the collection to the Belgian Government and became part of the autonomous Royal Natural History Museum in 1846, known as the Royal Belgian Institute of Natural Sciences since 1948. Fieldwork by researchers and collaborators, in Belgium and abroad, donations and purchases have been expanding the assets ever since. The data presented in this dataset are coming from the DaRWIN database, the collection management tool of the RBINS. Today, DaRWIN manages information on about 550.000 specimens stored in the institute's repositories. This number rises on a daily basis thanks to the continued efforts of curators and their adjuncts that are responsible for maintaining the stored specimens and information. The dataset is made available on GBIF and covers the complete collection, as well as subcollections within Vertebrates (mammals, birds, reptiles, amphibians and fish), Invertebrates (acarines, arachnids, Belgian marine invertebrates, brachiopods, bryozoans, marine chelicerates, cnidarians, crustaceans, echinoderms, molluscs and rotifers) and Entomology (beetles, dipterans, heterocerans, hymenopterans, orthopterans and rhopalocerans).