The aim of this study was to evaluate the efficacy of sour tea supplementation in patients with nonalcoholic fatty liver disease (NAFLD). Seventy NAFLD patients were enrolled in this randomized, double-blind, placebo-controlled clinical trial. Participants received sour tea in the form of a 450 mg capsule or a placebo capsule daily for 8 weeks. Anthropometric indices, liver enzymes, lipid profile, blood pressure, and antioxidant status were evaluated at the baseline and at the end of the study. Sixty-one participants completed the study. After 8 weeks, sour tea administration significantly decreased serum triglyceride (TG) (p = .03), alanine aminotransferase (ALT) (p = .01), and aspartate aminotransferase (AST) (p = .004) levels compared with the placebo. In addition, sour tea supplementation resulted in a significant reduction in systolic blood pressure (SBP) (p = .03) and diastolic blood pressure (DBP) (p = .04), and a significant increase in serum total antioxidant capacity (TAC) levels (p ˂ .001) compared with the placebo. However, no significant changes in anthropometric measures, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c), and high-density lipoprotein cholesterol (HDL-c) levels were observed after sour tea supplementation compared with the placebo (p > .05). Sour tea supplementation may be effective in improving serum TG, liver enzymes, and blood pressure in patients diagnosed with NAFLD. Further studies are needed to address the exact mechanism of action of these effects.