Abstract Background: Data on diet quality and pancreatic cancer are limited. We examined the relationship between diet quality, assessed by the Healthy Eating Index-2015 (HEI-2015), the Alternative Healthy Eating Index-2010 (AHEI-2010), the alternate Mediterranean Diet (aMED) score, the Dietary Approaches to Stop Hypertension (DASH) score and the energy-adjusted Dietary Inflammatory Index (E-DII), and pancreatic cancer incidence in the Multiethnic Cohort Study. Methods: Diet quality scores were calculated from a validated food frequency questionnaire administered at baseline. Cox models were used to calculate HR and 95% confidence intervals (CI) adjusted for age, sex, race/ethnicity, education, diabetes, family history of pancreatic cancer, physical activity, smoking variables, total energy intake, body mass index (BMI), and alcohol consumption. Stratified analyses by sex, race/ethnicity, smoking status, and BMI were conducted. Results: Over an average follow-up of 19.3 years, 1,779 incident pancreatic cancer cases were identified among 177,313 participants (average age of 60.2 years at baseline, 1993–1996). Overall, we did not observe associations between the dietary pattern scores and pancreatic cancer (aMED: 0.98; 95% CI, 0.83–1.16; HEI-2015: 1.03; 95% CI, 0.88–1.21; AHEI-2010: 1.03; 95% CI, 0.88–1.20; DASH: 0.92; 95% CI, 0.79–1.08; E-DII: 1.05; 95% CI, 0.89–1.23). An inverse association was observed with DASH for ever smokers (HR, 0.75; 0.61–0.93), but not for nonsmokers (HR, 1.05; 0.83–1.32). Conclusions: The DASH diet showed an inverse association with pancreatic cancer among ever smokers, but does not show a protective association overall. Impact: Modifiable measures are needed to reduce pancreatic cancer burden in these high-risk populations; our study adds to the discussion of the benefit of dietary changes.