Abstract Disclosure: M. Shaheen: None. K. Schrode: None. D. Pan: None. S.M. Najjar: None. T.C. Friedman: None. Societies of the liver recommended replacing the term non-alcoholic fatty liver disease (NAFLD) with metabolic dysfunction-associated steatotic liver disease (MASLD). This study aimed to investigate the trends in the MASLD prevalence by racial/ethnic among the U.S. adult population overtime. We analyzed data from 32,726 adults in National Health and Nutrition Examination Survey 1988-2018. Hepatic steatosis (HS) was diagnosed using the U.S. Fatty Liver Index. MASLD was diagnosed in individuals with both HS and at least one of the following: overweight/obesity, diabetes mellitus, hypertension, high triglyceride or HDL-Cholesterol or in treatment. Logistic regression was used to test for trends over time for the overall sample and for each racial/ethnic group accounting for design and sample weights. Prevalence estimates were age-adjusted using the direct standardization based on census data. We also estimated the percent change in the adjusted prevalence (change in the adjusted prevalence/baseline adjusted prevalence)*100. The study showed that over the study period, the age-adjusted prevalence of MASLD significantly increased from 16% in 1988 to 38% in 2018, representing a 138% percent increase. Concurrently, the age-adjusted prevalence of obesity increased from 23% in 1988 to 40% in 2018 reflecting a 74% increase (p<0.05). Among Mexican Americans, the age-adjusted MASLD prevalence consistently exceeded that of the overall population and other racial/ethnic groups. Significant increase in the percent change of the age-adjusted prevalence of MASLD was observed across all racial/ethnic groups (Mexican Americans=69%; Blacks=117%; Whites=140%) except Other Hispanics (no change). The age adjusted prevalence of obesity also increased significantly in all racial/ethnic groups (% change: Mexican Americans=58%; Other Hispanics=18%; Blacks=59%; Whites=77%) (p<0.05). Our findings indicated an increase in the age-adjusted prevalence of MASLD over time that surpassing the increase in obesity prevalence. These disparities warrant further investigation and targeted interventions to address MASLD effectively. Grants: R01MD012579, R24DA017298, U54MD007598, S21MD000103, UL1TR001881 Presentation: 6/2/2024