Lasse Marhaug (born September 10, 1974) is a Norwegian musician who primarily works in the field of noise music but frequently drifts into other areas such as improvisation, jazz, rock and extreme metal. Marhaug has also been involved in creating music for theatre, dance, art installations and video art. Active since the early 1990s, he has participated as a performer and composer on over 200 releases in CD, vinyl and cassette tape formats.
Marhaug tours extensively, and is a frequent collaborator. He currently participates in the projects Jazkamer/Jazzkammer, Nash Kontroll (with Mats Gustafsson and Dror Feiler), DEL, and Testicle Hazard. Defunct projects include Origami Replika and Lasse Marhaug Band. Other collaborative partners include Merzbow, Sunn O))), Carlos Giffoni, Maja Ratkje, Alan Courtis, Marc Broude, Ronnie Sundin, Nordvargr, Kommissar Hjuler und Frau, The Skull Defekts and John Wiese.
In 2007 Norwegian newspaper Dagsavisen rated Marhaug's album The Shape of Rock to Come as number 19 on their list of the best albums in Norwegian history.