Adherence to a Mediterranean-style diet is associated with a lower risk for mortality, cognitive decline, and dementia. Whether adherence to a Mediterranean-style diet protects against age-related frailty is unclear. Therefore, our objective was to examine the association between a Mediterranean-style diet with the risk of frailty in community-dwelling older persons. We conducted longitudinal analyses using data from 690 community-living persons (≥65 y) who were randomly selected from a population registry in Tuscany, Italy. Participants of the Invecchiare in Chianti study of aging completed the baseline examination in 1998-2000 and were re-examined at least once over 6 y. Adherence to a Mediterranean-style diet (scored 0-9, modeled categorically as ≤3, 4-5, and ≥6) was computed from the European Prospective Investigation into Cancer and nutrition FFQ previously validated in this cohort. Frailty was defined as having at least 2 of the following criteria: poor muscle strength, feeling of exhaustion, low walking speed, and low physical activity. After a 6-y follow-up, higher adherence (score ≥6) to a Mediterranean-style diet was associated with lower odds of developing frailty [OR = 0.30 (95% CI: 0.14, 0.66)] compared with those with lower adherence (score ≤3). A higher adherence to a Mediterranean-style diet at baseline was also associated with a lower risk of low physical activity (OR = 0.62; 95% CI: 0.40, 0.96) and low walking speed [OR = 0.48 (95% CI: 0.27, 0.86)] but not with feelings of exhaustion and poor muscle strength. In community-dwelling older adults, higher adherence to a Mediterranean-style diet was inversely associated with the development of frailty.