We investigated the rates of lipodystrophy events, according to mitochondrial DNA haplogroup, in 187 patients starting combination antiretroviral therapy and following it. Incidence rates of lipoatrophy and fat accumulation were 8.2 and 4.8 per 100 person-years of follow-up, respectively. In multivariable models, patients with haplogroup K were at higher risk of any lipodystrophy [adjusted relative risk (aRR) 4.02, P = 0.0009], lipoatrophy (competing-risk aRR 2.42, P = 0.09; cause-specific aRR 2.99, P = 0.031), and fat accumulation (competing-risk aRR, 2.63, P = 0.11; cause-specific aRR 5.27, P = 0.019) than those with haplogroup H. Mitochondrial haplogroups may explain part of the genetic predisposition to lipodystrophy during combination antiretroviral therapy.