Seaweed is a food that is widely consumed by Asian people and has many health benefits, including lipid and glycemic reduction, but the effect of seaweed on non-alcoholic fatty liver disease (NAFLD) has not been widely discussed. This study aims to compare the effect of seaweed consumption on improving liver injury in NAFLD patients. The primary outcome is the change of liver enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST], alkaline phosphatase [ALP], and g-glutamyl transferase [GGT]), while the secondary outcome includes body weight, waist circumstance, body mass index (BMI), lipid profile, insulin level, and insulin sensitivity and any related metabolic indicators. There was significant liver improvement in the intervention group, but some parameters from secondary outcomes showed no significant effect. Further studies with larger and heterogeneous populations are still needed to confirm the effectiveness of seaweed supplementation in NAFLD patients.