Background: Therapist requires accurate, cost-effective and valid tools to assess the knee joint position-sense in participants with patellofemoral pain (PFP). OBJECTIVE: to evaluate the reliability and validity of computer-aided design (Autocad) software in assessing knee position sense in participants with (PFP) against an isokinetic-dynamometer (IKD) procedure. Design: Cross-sectional, validity and reliability study. Setting: Isokinetic laboratory. Participants: Thirty-nine participants (11 males and 28 females) ranging in age from 18 to 35 years old participated in the study. On two separate occasions, two days apart, all subjects were evaluated by the same examiner. Main Outcome Measures: Knee joint position sense by isokinetic dynamometer (IKD) and Autocad software at angle 20º and 60º. Intra-tester reliability was obtained by intraclass correlation coefficient (ICC) and standard error of measurement (SEM). RESULTS: Validity was determined using the Pearson product-moment relationship, which revealed a moderate to good association (0.60) between the isokinetic dynamometer (IKD) and computer-aided design software at 20º and a good to excellent association (0.79) at 60º. Intrarater reliability coefficients (ICC) were (0.64) at 20º and (0.50) at 60º, indicating a moderate to good association at both angles with a standard error of measurement of (2.2) degree at 20º and (2.9) degree at 60º.CONCLUSION: computer-aided design software had high accuracy, a low exam cost, and not involves radiation exposure. These findings support using this method for examining joint position sense. Therefore, Therapist does not need expensive methods to obtain representative JPS abilities.