Background: The prevalence of obesity has rising trends worldwide in almost every country in all the age groups. The objectives of the present study were to know the prevalence of obesity and overweight among students and to assess knowledge of these students regarding hazards of obesity and its preventive measures before and after educational interventional training.Methods: The present interventional study was undertaken during September 2016 to December 2017 in randomly selected 3 Government Arts Colleges of Patan, Ahmedabad and Vadodara city of Gujarat state, India. Total 313 students between the age group of 18 to 23 years were examined and body mass index were calculated. The prevalence of overweight and obesity were determined based on the International Obesity Task Force criteria. Single educational training for 45 minutes was given to the students and their post-intervention knowledge for same was assessed after the training. Thus collected data was analyzed using SPSS 17 (trial version).Results: Overall, the prevalence of obesity and overweight was 9.9% and 14.6% respectively. Baseline knowledge of the students regarding hazards of obesity like hypertension, cancer, myocardial infarction and diabetes mellitus was 19.5%, 18.8%, 17.3% and 16.6% respectively which was significantly increased to 91.4%, 94.2%, 96.2% and 96.8% respectively after the intervention. Baseline knowledge of the students regarding preventive measure of obesity like avoiding junk food/ healthy diet, exercise and meditation was 25.2%, 27.2% and 30.7% respectively which was significantly increased to 96.5%, 99.7 and 98.7% respectively after the intervention.Conclusions: Single educational session has increased the knowledge regarding hazards of obesity and its preventive measures among college students significantly.