Dag Syver Arnesen (born 3 May 1950) is a Norwegian jazz pianist with a series of album releases.

[1][2] Arnesen was born in Bergen, and studied classical piano under Jiri Hlinka at the Bergen Music Conservatory and got a commitment[1] by Den Nationale Scene.

Eventually he went to jazz and played in the 1970s with the Arvid Genius' orchestra, and led his own Trios, Quartets and Septetter og 13'tets.

Arnesen has also lived in Oslo and played in the jazz bands Søyr, Orleysa, various groups led by Norwegian guitarist Thorgeir Stubø, vocalist Susanne Fuhr, saxophonists Knut Riisnæs and Odd Riisnæs and orchestra leader Kjell Karlsen.

In the Bergen-based Sigurd Ulveseth Quartet he has participated on three releases, and Arnesen also led the local Evans Jazzclub.