Aims: Previous studies have suggested consumption of red meat might be associated with an increased risk of developing nonalcoholic fatty liver disease (NAFLD). However, large-scale, prospective data regarding red meat consumption in relation to the incidence of NAFLD are lacking, nor is it known whether this association is mediated by obesity. Methods: This prospective cohort study included 77,795 women in the Nurses’ Health Study II cohort without NAFLD at baseline (in 1995), who provided detailed, validated information regarding diet, including consumption of red meat, every 4 years, through 2015. Lifestyle factors, clinical comorbidities and body mass index (BMI), were updated biennially. Cox proportional hazard models were used to estimate multivariable adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs). Results: Over 1,444,637 person years of follow-up, we documented 3,130 cases of incident NAFLD. Women consuming ≥2 servings of red meat per day had a 56% higher risk of developing incident NAFLD compared to women consuming ≤1 serving per week (95% CI, 1.26-1.93), after multivariable adjustment. Similarly, significant and positive associations were observed for both unprocessed and processed red meat (both P-trend< 0.0001). However, after further adjustment for BMI, all associations for red meat, including unprocessed and processed red meat, were attenuated and not statistically significant (all P-trend >0.05). BMI was estimated to mediate 66% (95% CI, 41.9%-83.9%; P<0.0001) of the association between red meat consumption and NAFLD risk. Conclusions: Red meat consumption, including both unprocessed and processed red meat, was associated with significantly increased risk of developing NAFLD. This association was mediated largely by obesity.