Background and Objective Obesity is the new epidemic globally. Obesity has also been linked to increased leg swing velocity higher metabolic expenditure and poorer postural stability all of which might affect foot function. Therefore this study was planned to determine the relationship between body mass index and foot posture index among healthy adults in the age group of 20-30 years studying at a medical university.Methods The study was conducted in the outpatient department of orthopaedics and physiotherapy SDM College of Medical Sciences and Hospital Dharwad India. This study was an observational cross-sectional study which included 50 healthy adult participants in the age group of 20-30 years based on the eligibility criteria. BMI was calculated using the Quelets index and foot posture scoring was done to determine the foot mass index. Descriptive analysis was done and presented as mean and standard deviation. Pearson correlation was done to determine the correlation between BMI and foot posture index. P less than 0.05 was considered significant.Results Increased body mass index was positively correlated with right and left foot posture indices. Conclusion Increased BMI leads to pronation of the feet. This can further cause the individual to walk slightly on the outside of the foot instead of the feet flat on the ground.