Björn Johan Andrésen (26 January 1955 – 25 October 2025) was a Swedish actor and musician. He was best known for playing the fourteen-year-old Tadzio in Luchino Visconti's 1971 film adaptation of the Thomas Mann novella Death in Venice.

Andrésen had only appeared in one film, En kärlekshistoria (1970) at the time he was cast in Death in Venice, which gained him international recognition. While the film performed relatively poorly at the box office, Andrésen was noted for his performance as Tadzio, the beautiful young Polish boy with whom the film's older protagonist Gustav von Aschenbach becomes obsessed. Film historian Lawrence J. Quirk commented in his study The Great Romantic Films (1974) that some shots of Andrésen "could be extracted from the frame and hung on the walls of the Louvre or the Vatican".