Truls Otterbech Mørk (born 25 April 1961) is a Norwegian cellist.
He was born in Bergen, Norway, the child of two professional musicians. Mørk started studying with Frans Helmerson at 17 at the renowned Edsberg Music Institute. An admirer of Mstislav Rostropovich and the Russian school of cello, Mørk went on to study with the Russian cellist Natalia Schakowskaya. He won several prices and became the first Skandinavian musician to reach the finals of the Tchaikovsky Competition in Moscow. At present, Mørk is ubiquitous on the international concert scene. His extensive discography spans from a Grammy‐award‐winning recording of the Shostakovich Cello Concertos to a critically acclaimed recording of Bach's Suites for Solo Cello. Mørk's passionate interest in chamber music led to the foundation of the International Chamber Music Festival of Stavanger. Mørk plays a rare Domenico Montagnana (Venice, 1723) cello, the scroll of which was made by Stradivarius.