Body mass index (BMI) and sleep duration are closely related health factors that have garnered significant attention in recent years due to their implications for public health. While high BMI has been hypothetically associated with shorter sleep duration in adults, limited studies have been conducted among boarding school students primarily due to variation in their daily routine. Therefore, this study aims to investigate the sleep duration among first-year secondary students at Kolej PERMATA Insan using a survey and determine whether BMI contributes to this issue. Demographic data including gender, height, and weight were then analysed using descriptive analysis. The BMI was calculated and classified as underweight, normal, overweight and obese based on the Malaysian population standards. An Anova test was employed to explore the relationship between BMI and sleep duration. The analysis revealed that the mean sleep duration for the 65 students was 5 hours 21 minutes, with a standard deviation (SD) of 1 hour 5 minutes. Male students slept significantly longer with a mean (SD), 5 hours 13 minutes (1 hour 52 minutes), compared to female students, who had a mean (SD) of 4 hours 46 minutes (1 hour 49 minutes) (p=0.05). However, no significant relationship was found between BMI categories and sleeping duration among first-year students. This study emphasized that gender, which influences different lifestyles, may contribute to sleep duration but BMI does not appear to play a significant role in this context. Future study may further investigate the relationship between BMI and sleep duration considering gender-specific factors.