Mats Theselius (born 1956) is a Swedish designer whose work moves between furniture, art, and architecture. Trained in furniture and interior design at Konstfack in Stockholm, he is best known for expressive chairs that pair bold forms with unexpected materials. His often limited-edition designs for Källemo, including the Elk Skin Chair, have made him a distinctive voice in contemporary Swedish design. His work is held in museum collections in Sweden and abroad.