Background: Transition to university, academic performance pressure, lack of sleep, personal relationships, and poor coping skills are the common sources of stress for undergraduate students. The health of students can be negatively impacted by high-energy, high-salt diets, irregular diets, and insufficient physical activity (PA), which can result in overweight and obesity. Aims and Objectives: To find out the relationship between PA and stress among medical students. Materials and Methods: The study was conducted on 60 male undergraduate students in the age group 18–21 years of 1st professional MBBS. After taking a detailed history body mass index (kg/m2) was calculated. Then subjects were asked to fill out the perceived stress scale and global PA questionnaire to assess their stress and PA status. Results: In the present study there is a statistically significant relationship between the stress score and the PA. This shows that those students who were leading a more active daily or weekly schedule were exhibiting lower scores on the stress scale tool employed. Conclusion: The study revealed a highly significant (P < 0.001) correlation between the stress level and PA status of the students.