Weight-related outcomes were examined among high school students in Minnesota public school districts according to the quality of district wellness policies. Wellness policy strength and comprehensiveness were scored using the Wellness School Assessment Tool (WellSAT) for 325 Minnesota public school districts in 2013. The associations between WellSAT scores and district-level means of high school student responses to a statewide survey of health behaviors were examined in this ecologic study. WellSAT Total Strength and Total Comprehensiveness scores were positively associated with both student mean Body Mass Index (BMI) percentile (Strength: P = 0.018, Comprehensiveness: P = 0.031) and mean percent overweight or obese (Strength: P = 0.008, Comprehensiveness: P = 0.026), but only in districts with >50% of students eligible for Free or Reduced-Price Lunches (FRPLs), or 'high FRPL districts'. WellSAT Physical Education and Physical Activity subscale scores were also positively associated with the mean days per week students engaged in physical activity for ≥ 60 min in high FRPL districts (Strength: P = 0.008, Comprehensiveness: P = 0.003) and in low FRPL districts (<35% eligible) for Strength score: (P = 0.027). In medium FRPL districts (35-50% eligible), Nutrition Education and Wellness Promotion Strength and Comprehensiveness subscale scores were positively associated with, respectively, daily servings of vegetables (P = 0.037) and fruit (P = 0.027); and WellSAT Total scores were positively associated with daily vegetable servings (Strength: P = 0.037, Comprehensiveness: P = 0.012). Administrators of economically disadvantaged school districts with a higher percentage of overweight students may be recognizing the need for stronger wellness policies and the specific importance of implementing policies pertaining to physical activity as a means to improve student health.