Endothelial dysfunction is closely linked to the development of atherosclerosis. This systematic review and meta-analysis reviewed the evidence on the effect of weight loss, achieved by dietary-based interventions, on biomarkers of endothelial function (EF). Two databases (Medline, Embase) were searched from inception until November 2022 for studies that met the following criteria: 1) adult subjects (≥ 18 years) without exclusion for health status, 2) dietary interventions for weight loss, and 3) measurements of changes in EF biomarkers. Random-effect meta-analysis and meta-regression were performed. Thirty-seven articles including 1449 participants were included in the systematic review. Study duration ranged from 3-52 weeks. Overall, weight loss significantly improved biomarkers of EF [standardised mean difference (SMD):0.65; 95%CI:0.49,0.81; P < 0.001;I 2 = 91.9%]. Subgroup analyses showed weight loss significantly improved levels of E-selectin (P < 0.001), intercellular adhesion molecule-1 (ICAM-1) (P < 0.001), vascular cell adhesion molecule-1 (VCAM-1) (P < 0.001), nitrite/nitrate (NOx) (P < 0.001) and vascular endothelial growth factor (VEGF) (P < 0.001). Conversely, there was no significant improvement for von Willebrand Factor (vWF). Meta-regression analysis revealed that changes in EF biomarkers were not affected by age, BMI, quality of the studies or the amount of weight lost. A significant heterogeneity was observed for the effects of weight loss on changes in EF biomarkers. Dietary-induced weight loss may be associated with biomarkers changes indicating an improvement of EF, and it may represent a potential strategy to reduce atherosclerotic risk.