The scientific collections comprise 2.5 million specimens divided into:

• Algae & cyanobacteria 102 000
• Bryophytes 149 000
• Fungi 63 000
• Lichens 170 000
• Vascular plants 2 000 000

The herbarium contains plants from all over the world. The collections from the Nordic countries are particularly extensive, but there are also important collections from, for example, the Mediterranean region, South Africa, Western Australia and parts of South America.

Three historical collections are kept separately due to their particular value:

• The Agardh Herbarium - one of the world's most important collections of algae.
• The Retzius Herbarium - mainly collected during the late 18th century.
• The Acharius Herbarium - mainly vascular plants from the 18th and early 19th century.

Paul Sintenis’ collections from Greece, Turkey and Turkmenistan are also often requested, just as Ludwig Preiss’ collections from Australia. More recently, important collections have been made within the projects Flora Hellenica and Flora of Scania. The collections of bryophytes, fungi and lichens are also growing continuously thanks to research projects and floristic inventories.

Work is in full progress to digitize the collections and make them available on the net. Currently, 34 % of the collections have been databased. New accessions are always digitized before being intercalated in the herbarium.