The effects of excessive alcohol consumption on the prognosis of metabolic dysfunction-associated fatty liver disease (MAFLD) remain unclear. We investigated all-cause and cause-specific mortality according to the amount of alcohol consumed by Asian individuals with MAFLD. This nationwide retrospective study included 996,508 adults aged 40-79years who underwent health check-ups between 2009 and 2012. Participants were categorized by the alcohol consumption-non-alcohol, moderate alcohol, and heavy alcohol group (≥ 30g/day for men, ≥ 20g/day for women) and by the combination of the presence or absence of MAFLD. Hepatic steatosis was defined as the fatty liver index ≥ 30. Cox analyses were used to analyze the association between alcohol consumption and MAFLD and all-cause and cause-specific mortality. MAFLD significantly increased all-cause, liver-, and cancer-related mortality. Individuals with both MAFLD and heavy alcohol consumption expressed the highest mortality risk in liver-related mortality compared to non-MAFLD and non-alcohol group (adjusted hazard ratio (HR), 9.8; 95% confidence interval (CI), 8.20-12.29). Regardless of MAFLD, heavy alcohol consumption increased the risk of liver- and cancer-related mortality. MAFLD and heavy alcohol consumption increased all-cause, liver-, and cancer-related mortality. Heavy alcohol consumption and MAFLD synergistically increase liver-related mortality.