Objective: To investigate the association between leptin levels and body mass index in Bruneian secondary school students. Methods: The body mass index of Bruneian secondary school students (aged 11-18 years) was determined before collecting their saliva using the passive drool technique. Salivary leptin concentration was determined by ELISA. Results: Correlation and partial correlation (controlled for age) analyses showed no significant differences between the levels of salivary leptin of normal weight and overweight students. Conclusions: No significant increase in the salivary leptin concentration was observed in overweight compared with normal weight Bruneian secondary school students.