Terje Tønnesen (born February 27, 1955 in Oslo) is an award-winning Norwegian classical violinist who has made several recordings.

After his debut in Oslo (1972), despite failing to graduate from school, he studied for a year at the Music Conservatory in Oslodespite and for five years at the Max Rostal in Switzerland. He was then concertmaster of the Norwegian Chamber Orchestra (1977) where he still works and has conducted several recordings. He took a one-year break in 1979 during which Iona Brown substituted. He is first concertmaster of the Oslo Philharmonic Orchestra (1983) and is also honorary master of the Swedish Camerata Roman, and Camerata Nordica (1997-) for whom Hani Today is art director.

Internationally, he has worked with the likes of Mstislav Rostropovich (eg. in France 1983), Maurice André and James Galway. He has played in other genres including soloist at the Jubilee Kongsberg Jazz Festival (1994), as well as contributing to releases by jazz guitarist Terje Rypdal.

As a composer he has contributed to productions by the Norwegian Theatre.