Background: Several studies have shown associations between Parkinson Disease (PD) risk and individual foods and nutrients with inconsistent results.Objective: We examined associations between dietary patterns and risk of PD in the Health Professionals Follow-Up Study (1986–2002) and the Nurses’ Health Study (1984–2000).Design: We included 49 692 men and 81 676 women free of PD at baseline and used principal components analysis to identify major dietary patterns and the Alternate Healthy Eating Index (AHEI) and the alternate Mediterranean Diet Score (aMed) to assess diet quality. Relative risks (RRs) were computed by using Cox proportional hazards models within each cohort and were pooled by using a random-effects model.Results: We documented 508 new PD cases after 16 y of follow-up. The principal components analysis identified 2 dietary patterns: prudent and Western. The prudent dietary pattern, characterized by high intakes of fruit, vegetables, and fish, was inversely associated with PD risk, but the Western pattern was not. The pooled multivariate-adjusted RR for the top compared with the bottom quintiles of the prudent score was 0.78 (95% CI: 0.56, 1.07; P for trend = 0.04). For the AHEI, the pooled multivariate-adjusted RR for the top compared with the bottom quintile was 0.70 (95% CI: 0.51, 0.94; P for trend = 0.01) and for aMED was 0.75 (95% CI: 0.57, 1.00; P for trend = 0.07).Conclusions: Dietary patterns with a high intake of fruit, vegetables, legumes, whole grains, nuts, fish, and poultry and a low intake of saturated fat and a moderate intake of alcohol may protect against PD. Benefits of a plant-based dietary pattern including fish to PD merit further investigation.