From its foundation, the Institute has dedicated special care to the gradual collection, sorting out, safe-keeping and protection of ethnographic materials. The materials that are in question here are ones that have been collected during the course of the regular research activities of the Institute, but are also transcribed materials and materials previously recorded from other archives, donated materials and purchased materials. Today these materials, which have been methodically collected over the last sixty years of the Institute's existence, create a unique collection of folklore and ethnographic documents that describe Croatian traditional culture in the twentieth century, about other nationalities in Croatia, as well as about Croats living outside of Croatia. The entire collection has been registered as a cultural monument. The material that makes up the manuscript collection contains 1990 text collections and music annotations, 19 dance collections and 374 kinetograms. As well as this, there are 57 drawing collections with about 2000 panels; 3910 tape recordings (which consists of mainly music recordings, but contains narratives); a record library with 1044 sound recordings; a photo library and a slide library with 61883 items in total; 1533 video cassettes and 51 films. The collection covers the areas of music, dance, oral and folk literature, folklore theatre, visual expression, traditional customs and the documentation of contemporary traditions and events. All these details about the collection are stored in a database, which is being continuously updated and enlarged, and thanks to which, makes research into the collections and archives very simple and quick.
In 1997 for preservation reasons, and also to make the collection more accessible, the project of digitalising and restoring the audio fund started. At the end of 2002, the digitalisation of the unique music annotations started. There are also plans to digitalise the video and photo libraries, but the progress of this new project is dependent on financial considerations.
The materials of the Institute are made available as a priority to the members of the Institute for their work in ethnographic and folklore research. Nevertheless, the collection is available for outside users, who are either members of establishments or individuals, interested in using them for the purpose of science, education, arts and culture, as well as those interested in amateur culture.