[Summary]: The Botanical Department at the former Royal Museum of Natural History in Sofia was opened on June 1st 1919 following the initiative of the Director of the Museum Dr. Ivan Buresch and existed up to 1947, when it merged with the newly founded Institute of Botany at the Bulgarian Academy of Sciences. One of the major contributions of the department from that period was the building up of a large herbarium, based on the collections of the first Bulgarian botanists-florists. At present it is a part of the herbarium of the Institute of Botany at the Bulgarian Academy of Sciences. The Botanical Department was responsible for active research in the study of the flora and vegetation of Bulgaria, begun by B. Davidov, B. Ahtarov, and N. Stojanov. A specialized library in botanical studies was also begun. A Botanical Section was restored at the National Museum of Natural History in 1975. The botanical exposition was opened for the first time in 1980. The building up of a herbarium, which at present has the largest collections of lichens (about 4000 exicata), as well as a national xylotheque has begun.