A 52-year-old woman also suffered minor injuries in the attack at Hornsjø Høyfjellshotell in Øyer, 200 kilometres north of Oslo.
Police said the stabbing occurred after a dispute between the student and the 54-year-old man, a member of staff at the Travelling Folk High School. Some thirty people connected to the school were staying at the hotel, local newspaper Gudbrandsdølen Dagningen reports.
Several armed police units arrived at the scene after receiving reports at 11.30pm of a serious stabbing incident.
The 23-year-old was arrested, while the 54-year-old victim was found critically injured after being stabbed in the back. Paramedics at the scene were unable to save his life.
The suspect faces a preliminary charge of causing bodily harm resulting in death. A remand hearing will be held on Wednesday.
The Travelling Folk High School is affiliated with Tvind, a controversial Denmark-based educational establishment set up in the 1970s to help combat poverty in the developing world. Critics have described it as a left-wing extremist sect.