Oxidative stress gained the attention recently in behavioral medicine and been contributes to various psychological disturbances and mental stress in Medical and Dental students. This study is to evaluate the level of oxidative stress markers in undergraduate students caused by examination stress. This cross sectional study was conducted at Priyadharshini Dental College. Fifty healthy final year dental students were participated and the level of oxidative stress (Lipid peroxidation and Antioxidant status) were assessed on the day of examination “stress condition” and compared with the same parameters obtained from the same students after the exam “non-stress condition”. The results shows that oxidative damage and sensitivity to lipid oxidation were significantly increased in “stress condition” (P<0.05) when compared with the same parameters in “nonstress” conditions. A significant decrease in plasma antioxidant level was observed (P<0.05) under stress. There is significant higher in oxidative stress its adversely affects the student performance and mental health during the examination.