Aim: To evaluate the relationship between body mass index (BMI) and dental development in the children in age-group of 6–13 years of Malwa region. Materials and methods: A total of 250 orthopantomograms (OPGs) of children aged 6–13 years (130 males and 120 females) collected from the Department of Paediatric and Preventive Dentistry, Government College of Dentistry, Indore, Madhya Pradesh, India, who came for their routine dental treatment. The chronological age, height, and weight were recorded, followed by calculating the BMI of each patient using Centers for Disease Control and Prevention (CDC) growth charts. The dental age was calculated using Cameriere's method. The comparison of the dental and chronological age was done using Wilcoxon signed-rank test. Results: The dental age of underweight patients was significantly lesser than that of the normal, overweight, and obese patients (p-value of <0.05). The dental age of the obese patients were greatest and significantly greater than that of the underweight, normal, and overweight patients (p-value of <0.05). Conclusion: Dental age is significantly associated with the BMI of children aged 6–13 years. The dental age of obese and overweight children is significantly greater than the chronological age. Clinical significance: Predicting the stage of dental development and eruption periods in children with mixed dentition can help with the sequencing and timing of orthodontic, prosthodontic, and surgical procedures.