Lasse Marhaug (born 10 September 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. He currently resides in Oslo.

Marhaug tours extensively, and is a frequent collaborator. He currently participates in the projects Nash Kontroll (with Mats Gustafsson and Dror Feiler), DEL, and Testicle Hazard. Defunct projects include Jazkamer/Jazzkammer, Origami Replika and Lasse Marhaug Band. Other collaborative partners include Tore Honoré Bøe, Marc Broude, Anla Courtis, Carlos Giffoni, John Hegre, Kommissar Hjuler und Frau, Merzbow, Paal Nilssen-Love, Nordvargr, Maja Ratkje, The Skull Defekts, Ronnie Sundin, Sunn O))), Ken Vandermark, Jon Wesseltoft, Runhild Gammelsæter, John Wiese, Jenny Hval and Kelly Lee Owens.