This study was designed to evaluate potential of Melissa officinalis L. (Lemon balm) infusion on the improvement of oxidative stress markers in workers occupationally exposed to aluminum (Al). In this before-after clinical trial, 30 Al workers were asked to drink Lemon balm infusion which was prepared like a tea bag twice per day (1.5 g/100 mL) for 30 days. Blood samples before and after entering the study were measured for lipid peroxidation (LPO), Total Antioxidant Capacity (TAC), Total Thiol Molecules (TTM), liver enzyme and some blood parameters. Use of Lemon balm infusion resulted in a significant increase in plasma levels of TTM and TAC and a significant decrease in triglyceride, cholesterol and aspartate transaminase (AST). LPO was not different before and after treatment. The conclusion is that infusions of Lemon balm improves oxidative stress condition in Al workers when used as a dietary supplement.