Background: Different dietary patterns have been associated with several health outcomes, including morbidity and mortality. There is little evidence on the association between empirically-derived dietary patterns and all cause mortality in Southern European populations.Objective: the aim of this study was to prospectively evaluate the association between an empirically-derived dietary pattern and all-cause mortality.Design: The SUN Project is an ongoing, multipurpose, prospective and dynamic Spanish cohort.Participants/setting: a prospective cohort of 16,008 middle-aged Spanish adults. All of them were former university graduates (alumni) (59.6 percent women, mean age: 38 years). Usual diet was assessed at baseline with a validated semiquantitative foodfrequency questionnaire.Main outcome measures: Deaths were confirmed by review of medical records and of the National Death Index.Statistical analyses performed: Dietary patterns were ascertained through a factor (principal component) analysis based on 30 predefined food groups. Participants were classified according to tertiles of adherence to the three main dietary patterns identified with factor analysis. Cox regression models were fitted to estimate multivariableadjusted hazard ratios (HR) and 95% confidence intervals (CI) for mortality.Results: Three major dietary patterns were identified: they were labelled Western dietary pattern (WDP) (rich in red and processed meat, potatoes and fast food), Mediterranean dietary pattern (MDP) (rich in vegetables, fish and seafood, fruits, and olive oil) and Alcoholic beverages dietary pattern (ABDP). During follow-up, 148 deaths were reported (mean age at death: 54.5 years). After adjustment for potential confounders, the lowest risk of all-cause mortality was found in the tertile of highest adherence to the MDP (adjusted HR for third vs. first tertile: 0.53; 95% CI: 0.34-0.84) (p for trend <0.01). The WDP and ABDP showed no significant association with mortality.Conclusions: Greater adherence to an empirically-derived dietary pattern approaching the traditional Mediterranean diet was associated with a reduction in the risk of allcause mortality among middle-aged Mediterranean adults.