Cardiorespiratory fitness shows the overall cardiovascular, pulmonary fitness capacity and the ability to carry out prolonged exercises.The current study was conducted to examine the Physical Fitness Index in young female physiotherapy students using the Modified Harvard Step Test. OBJECTIVE:The objective of this study was to assess the Physical Fitness Index in female undergraduate Doctor Of Physical Therapy students. METHODS:Cross-sectional study was used. The sample size was 200 physiotherapystudents. Participants were selected through the Non-Probability Convenient sampling technique. Height (m) and Weight (kg) were measured to calculate BMI.The Modified Harvard Step test was used to calculate the Physical Fitness Index. SPSS 21 was used for statistical analysis. RESULTS: The current studyshows that the Mean age of the participants was 21.53 ±1.83 with a minimum age of 17 years and maximum age of 26 years.4.5 %( n=9) students have excellent PFI, 13 %( n=26) students have Good PFI, 15 %( n=31) students have Fair PFI and 67 %( n=134) students have poor PFI. CONCLUSION:The physical fitness of physiotherapy students at Riphah College of Rehabilitation Sciences is inadequate, and overweight students have lower physical fitness than students with normal BMI.