Abstract: Regarding role of oxidative stress in operating room personnel and the anti oxidative stress potential of Cinnamon zeylanicum (cinnamon) in healthy subjects, the present study aimed to examine anti oxidative stress potential of cinnamon in operating room personnel. A group of 18 operating room personnel was invited to drink cinnamon (100 mg/300 mL tea) once daily for 10 days. Blood samples were obtained before and after entering the study and plasma was measured for oxidative stress biomarkers including Lipid Peroxidation Level (LPO), Total Antioxidant Power (TAP) and Total Thiol Molecules (TTM). Treatment of subjects with cinnamon induced a significant reduction in plasma LPO (5.03±2.01 vs. 3.25±1.32 nmol mL-1, p = 0.016). No statistically significant alteration was found for plasma TAP (1.24±0.12 vs. 1.28±0.12, p>0.05) and TTM (0.78±0.05 vs. 0.82±0.03, p>0.05) after 10 days treatment by cinnamon. In conclusion, reduction of cellular LPO by cinnamon as a dietary supplement can be a rational protocol to control source of hazards in operating room personnel.