Gustafsson was born in Goteborg, Sweden. He studied at the Calle Flygares Theater School in Stockholm to become an actor.  But before his debut as an actor, he had already debuted in 2005 as a stand-up comedian at Bungy Comedy, a Swedish club for stand-up beginners. In 2006 he enrolled at Standup Star, a stand-up school, where among others, Özz Nûjen and Jakob Öqvist, two of the most well-known comedians in Sweden, have attended. As of 2008, his most notable appearance was in Melodifestivalen 2008, the Swedish selections for the Eurovision Song Contest. For example, he sang a song to Kristian Luuk's (the host) girlfriend Carina Berg. In his song he declared his love for her. Afterward, Berg said that she had to hide her cheeks so people couldn't see that she was blushing. Gustafsson gained a certain degree of international fame following a World of Warcraft (WoW) joke in Parlamentet, talking about people wasting time on the internet and not contributing to their party's effort by playing inefficiently, using so much internal WoW terminology himself that he was incomprehensible to non-players. The scene was spread over the Internet, mainly on YouTube, where translations into other languages could also be found. In 2008, Björn received big media attention by great efforts in Parlamentet and as an entertainment in the breaks to Melodifestivalens and he also got voted as the Sweden's funniest man by Aftonbladet's readers on 6 March 2008. He also read the Swedish votes at the Eurovision Song Contest 2008. He continued his "stand-up" shows at the big stage, in the 44th Guldbagge Awards in 2009 together with Johan Glans, and with Robert Gustafsson in the Svenska idrottsgalan 2009 (Swedish athletics awards) where he also presented the nominations for rookie of the year.

Filmography

• 2025The Penguin Lessons — Tapio
• 2024Björnzone 2.0 — Self, Director
• Koppla av — Various
• Padel Dreams — Fabian
• Ture Sventon och den magiska lampan — Polisen Pär
• Ture Sventon och jakten på ungdomens källa — Agent-Pär
• Clark — Kaj-Robert
• Alla utom vi — Ola
• 2021Till Sun Rises — Henrik
• 2020Bert's Diary — Lynx / Lo
• 2020Nelly Rapp – Monster Agent — Vincent
• 2019Call Mom! — Manlig terapeut
• Ture Sventon and the Secrets of The Bermuda Triangle — Per
• 2018Becoming Astrid — Sture
• 2018Kingdom of Sweden — Various
• People of Earth — Don the White
• 2015Kung Fury — Private Lahmstache
• Other Space
• 2015Spy — Anton
• Barna Hedenhös uppfinner julen — Junior
• Svensk humor — Various roles
• 2012Cockpit — Albin
• Kontoret — Viking
• 2012Tina & Bettina: The Movie — Niklas
• Nissene over skog og hei — Håkan Holmgren
• 2011The Crown Jewels — Pettersson-Jonsson
• 2010Klown — Mandlig vært, Castello Alleycat
• 2009Kenny Begins — Lenny Starfighter
• Roast på Berns
• 2008Grown Ups — Johan
• Morgonsoffan
• 2006Beck 18 - The Girl in the Root Cellar
• Permafrost — Marcus Tell

Appearances as themselves (9)

• Bianca by Night — Self - Guest
• 2025Julallsång på Skansen — Self
• Carina Bergfeldt — Self - Guest
• Herngrens Husbil — Self
• 2017Skratta Då: En Rolig Historia Om Svensk Standup  — Self
• Parneviks — Self
• Historieätarna — Himself, Self
• Robins — Self - Guest
• Melodifestivalen — Self