Achille Compagnoni (26 September 1914 – 13 May 2009) was an Italian mountaineer and skier. Together with Lino Lacedelli on 31 July 1954 he reached the summit of K2. He is also noted for betraying his teammates Pakistani Amir Mehdi and Italian Walter Bonatti and leaving them in a life-threatening situation in order to ensure that he reached the summit first.