Mitochondrial haplogroups could influence individual susceptibility to mitochondrial DNA (mtDNA) damage, and human longevity, as indicated by previous studies with Caucasian (European) or Asian cohorts. Here, we compared the frequency of mtDNA haplogroups in a group of Spanish (Caucasian) centenarians (n = 65, aged 100-108 years, 58 women, most from the central part of Spain) and a group of healthy young adults (n = 138, 62 women, aged 20-40 years) of the same ethnic origin. We did not find significant differences between centenarians and the control group (P > 0.2). Only two centenarians (both women) had the haplogroup J, which hampered comparison with the control group (n = 15, five women). Our data confirm that the potential effects of mitochondrial haplogroups on human longevity might be population/geographic specific, with important differences between studies (notably, with regard to the previously reported potential benefit brought about by the haplogroup J) arising from the different living environment and ethnic background of the study cohorts.