The study was undertaken to assess the respiratory and sympathetic cardiovascular functions in obese and non obese school children of 12-16 years age group, randomly selected from two schools of Rajpura (Punjab), representing mixed socioeconomic group of Punjabi ethnicity and categorized as obese or controls as per standard criteria for Body Mass Index (BMI). Dynamic lung function tests and pressor response to cold (Cold pressor test) and isometric exercise (Handgrip dynamometer test) were carried out. Statistical analysis comprised students' t-test, at 95% confidence level and simple linear regression analysis. The results indicated significantly higher baseline diastolic blood pressure (DBP) (P < 0.004) in obese children correlating positively with BMI (r = 0.57). Significantly increased DBP response to applied cold stimulus (response/range, P < 0.02 and maximal value, P < 0.001) and borderline response to isometric exercise (P < 0.002) in obese children indicated autonomic instability. The dynamic lung functions were significantly decreased (P < 0.04) in obese subjects and correlated negatively with BMI. Personal data forms of obese children revealed less physical activity and excessive intake of junk foods. Thus it is concluded that obese children have derangement of sympathetic cardiovascular functions and reduced pulmonary functions.