Obesity continues to be one of the most important emerging public health problems over the past few decades in all developing countries, and recently in non developing countries also, because of improving living standerds. Lack of physical activity and leisurely attitude are one of the factors which determine the obesity and many factors influence the physical activity levels. The Leisure Time Physical Activities (LTPA) could be an important factor which decides energy balance, which can be influenced by self-perception of obesity. In this pilot study the impact of self-perception of obesity on LTPA (Kcal/week) using Compendium of Physical activities by Ainsworth et al was studied among medical students. The increased level of physical activity (LTPA) was observed among both genders with BMI less than 25; but female with overweight/obesity (BMI ≥ 25) showed significant correlation of LTPA with their BMI (r2 = 33.15%; p = 0.03). The subjects perceived their weight in proportion to their BMI especially male students. The subjects were grouped based on their self-perception of obesity, and significant correlation between self-perception of obesity and LTPA was observed among females who neither disagree, nor agree their obesity (group 3: r2 = 74.31%; p = 0.0003). Among males BMI was significantly different between the groups. Most of the male subjects perceived their overweight/obesity and more LTPA among those perceived not obese. Among females who perceived their overweight performed more LTPA to reduce their BMI. But in both gender those with BMI more than 25 and those strongly agree their obesity had less LTPA. Hence this study contends the impact of self-perception of obesity on LTPA among medical students and the importance of motivation for those who require intervening by improving their physical activities.