Background: Evidence regarding the individual and combined impact of dietary flavonoids on the risk of metabolic dysfunction associated with steatotic liver disease (MASLD) remains scarce. Our objective is to evaluate the association between individual and multiple dietary flavonoids with MASLD in adults. Methods: Data sets were obtained from the National Health and Nutrition Examination Survey (NHANES), 2017-2018. In total, 2581 participants aged over 18 years, with complete information on dietary flavonoid intake, MASLD, and covariates, were included. Flavonoid intake was energy-adjusted using the residual method. Logistic regression analysis was employed to examine the impact of total flavonoid intake on MASLD. Weighted quantile sum (WQS) analyses were used to evaluate the combined and individual effects of flavonoids on MASLD and to identify the predominant types with the most significant contribution to MASLD prevention. Results: The highest tertile of total flavonoid intake was associated with a 29% reduction in the risk of MASLD compared to the lowest tertile after multivariable adjustments (OR: 0.71, 95% CI: 0.51-0.97). The WQS analysis revealed that anthocyanidins, flavones, and flavanones were the most critical contributors among six subclasses (weights = 0.317, 0.279, and 0.227, respectively) and naringenin, apigenin, and delphinidin were the most critical contributors among 29 monomers. (weights = 0.240, 0.231, and 0.114, respectively). Also, a higher intake of anthocyanidins, flavones, naringenin, apigenin, and delphinidin was linked to a reduced risk of MASLD (p < 0.05).Conclusions: Our findings suggested that a higher flavonoid intake is associated with a lower risk of MASLD, with anthocyanidins, flavones, flavanones, naringenin, apigenin, delphinidin, and myricetin contributing most to the protective effects of flavonoids.