Background <p>The effects of resveratrol supplementation on anthropometric indices, adiponectin, and leptin levels remain inconclusive in individuals with overweight and obesity.</p> Method <p>This systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to evaluate the effects of resveratrol supplementation on anthropometric indices, adiponectin, and leptin levels. We searched electronic databases, including Scopus, Web of Science, and PubMed, up to September 2025, to identify eligible RCTs.</p> Results <p>A total of 23 RCTs, involving 1005 participants, met the inclusion criteria for the meta-analysis. Resveratrol supplementation did not significantly affect body weight (WMD: −1.42 kg; 95% CI: −3.19, 0.35; <i>P</i> = 0.117), body mass index (BMI) (WMD: −0.47 kg/m²; 95% CI: −0.96, 0.01; P = 0.055), fat mass (FM) (WMD: 0.47 kg; 95% CI: −1.75, 2.69; <i>P</i> = 0.679), body fat percentage (BFP) (WMD: −0.88%; 95% CI: −1.91, 0.15; P = 0.094), fat-free mass (FFM) (WMD: 1.42 kg; 95% CI: −1.04, 3.89; P = 0.257), waist-hip ratio (WHR) (WMD: -0.00; 95% CI: −0.01, 0.00; P = 0.436), adiponectin (WMD: 1.84 µg/mL; 95% CI: −2.25, 5.95; <i>P</i> = 0.378), or leptin (WMD: 1.87 ng/mL; 95% CI: −3.84, 7.60; P = 0.521). However, resveratrol supplementation significantly reduced waist circumference (WC) (WMD: −1.93 cm; 95% CI: −3.10, −0.76; <i>P</i> = 0.001). Subgroup analyses revealed significant reductions in body weight and BMI with doses &lt;1000 mg/day, longer interventions (≥12 weeks), and in females. Additionally, FFM increased significantly among participants aged &lt;50 years, and leptin levels were significantly elevated in both sexes.</p> Conclusion <p>This meta-analysis showed that resveratrol supplementation did not significantly impact most anthropometric measures and serum leptin and adiponectin in individuals with overweight and obesity. However, it led to a significant reduction in waist circumference.</p> <p>The PROSPERO registration number: is CRD42024497932.</p>