BACKGROUND: Metabolic dysfunction-associated steatotic liver disease is a significant driver of the increasing global burden of chronic liver disease. This study aimed to describe the temporal trends and inequalities of liver complications related to metabolic dysfunction-associated steatotic liver disease (LC-MASLD) by geographical region, age and sex during 1990-2021. METHODS: Global Burden of Diseases Study 2021 data were analysed to assess LC-MASLD incidence, prevalence, mortality and disability-adjusted life years (DALYs). Temporal trends during 1990-2021 were measured by 'estimated annual percentage change' (EAPC). Inequalities of LC-MASLD burden across countries were evaluated by the slope index of inequality (SII) and the relative concentration index (RCI). RESULTS: During 1990-2021, LC-MASLD rose annually by 0.73% in incidence and prevalence, 0.19% in mortality and 0.16% in DALYs. In 2021, the Middle East and North Africa had the highest incidence and prevalence and Andean and Central Latin America had the highest mortality and DALY rates. While LC-MASLD incidence was earliest in the 15-19 age group, both prevalence and DALY rates peaked at 75-79 years for both sexes. Inequalities in mortality and DALYs by countries' socioeconomic development index increased during 1990-2021, demonstrated by a decline in SII from -0.09 to -0.56 per 100 000 for mortality and from 1.41 to -7.74 per 100 000 for DALYs. RCI demonstrated similar findings. CONCLUSION: The LC-MASLD burden is increasing globally, especially in economically disadvantaged countries, with widening disease inequalities during 1990-2021. Effective prevention and subregional interventions are crucial, with a specific focus on resource optimisation for disadvantaged populations.