Floberg joined Det Norske Teatret (The Norwegian Theatre) in 1972, appearing in such plays as The Caretaker, When You Comin' Back, Red Ryder?, Long Day's Journey into Night, and Saint Joan of the Stockyards.
[4][5] In the 70's and 80's he appeared in several Norwegian films, playing alongside such actors as Sossen Krohg, Lars Andreas Larssen, Carsten Byhring, Frøydis Armand and Geir Børresen.
Floberg's breakthrough came when he played the title role in Telegrafisten (1993), another film directed by Gustavson, loosely based on Knut Hamsun's novel Sværmere.
[7] Floberg plays Ove Rolandsen, a telegraph operator and inventor, in a small coastal village in northern Norway, around the turn of the 19th century.
[9] In 1997 he appeared in the Norwegian crime film Insomnia, playing the antagonist Jon Holt, a famous author who claims to have had a close relationship to the murder victim.
The two men fell out over a perceived slight on Skarsgård's part allegedly regarding Floberg's sexual prowess, although neither party will comment on the incident in question.
[20] After I am Dina, Floberg appeared in Salmer fra kjøkkenet, a comedy / drama directed by Bent Hamer, starring Joachim Calmeyer as the grumpy old bachelor Isak.
To prepare his young team for their next production, a reality series, he takes them all to spend the weekend in an isolated cabin in the forest without food or cell phones.
Soon mysterious things begin to happen, as the team discovers an abandoned encampment, and eventually the body of a woman, by a nearby lake.
The film starred Nicolai Cleve Broch and Ane Dahl Torp, who were both nominated for Amanda Awards for Best Actor and Best Actress, respectively.
[30] Dagbladet's Inger Bentzrud commended the actors, but noted that all of Cleve Broch, Floberg, and Ahmed Zeyan played similar roles in Uno.
[31] One particularly negative review came from Bergens Tidende, who gave the film a 2/6 rating, highlighting Floberg's performance as one of the few positive points.
As chief inspector Jakob Hamre, he serves as a foil for shabby private investigator Varg Veum (Seim).
[36] The second theatrically released film in the series was Falne Engler (2008), directed by Morten Tyldum, with Floberg and Seim reprising their roles as Veum and Hamre.
Bjørn Floberg expressed his satisfaction with the films: "[The producers and directors] have set a new standard for this genre, and I would like to be a part of the continued development of the Varg Veum universe, together with the script writers, and not least Trond Espen, with whom I've had a very good cooperation".
[37] In 2010 he played alongside his long time film rival and personal enemy Stellan Skarsgård in the Norwegian black comedy A Somewhat Gentle Man.
In 2011, Floberg received the Committee's Honorary Amanda Award during the annual ceremony at the Norwegian International Film Festival in Haugesund.