Flow rates are very important factors which affect the volume and speed at which air is moved into and out of lung. Body Mass Index and Waist Hip ratio are the most commonly used parameters nowadays to assess obesity and the diseases associated with it. But both the parameters have the limitation of not distinguishing between fat compartment and muscle compartment. Hence this study was taken with the objective that which body composition parameter has highest correlation with flow rates.150 (85, males; 65, females)healthy medical students 18-24 years age group. Body fat percentage was assessed using „Bioelectric Impedance‟ technique.Analysis was done using “GraphPad Prism 6.0” Correlation coefficients and Linear regression equations were used. PEF, PIF & MIF50 have highest correlation with Fat Free Mass (FFM) followed by Fat Free Mass Index (FFMI). MEF25-75& MEF50 have insignificant correlation with all parameters.