Background: Knee is one of the largest and most complex joints in the body. Disease processes and injuries that disrupt ligaments, menisci, articular cartilage and other structures of the knee cause painful knee resulting in significant morbidity and disability. The present study was conducted to evaluate the efficacy of MRI in assessment of internal derangement of knee joint. Materials & Methods:70 patients with painful knee joint of both gendersunderwent MRI of knee joint with 1.5 Tesla high gradient MRI scanner. T1 and T2 weighted sequences in sagittal planes, PD weighted sequences in axial, coronal and sagittal planes and fat suppressed T2 or STIR sequences were recorded. The direct coronal, sagittal, and axial views are the three common imaging planes. We used a 16x16 cm field of view, a 256 x 256 matrix, and a 3 mm slice thickness to analyze the knee in these three planes. Results: Out of 70 patients, 32 were males and 38 were females. Age group 11-20 years had 7, 21-30 years had 15, 31-40 years had 24, 41-50 years had 14, and 51-60 years had 10 patients. The difference was non- significant (P> 0.05). Common knee pathologies were medial meniscal tears in 8, lateral meniscal tears in 7, marrow oedema in 9, joint effusion in 6, anterior cruciate ligament tear in 15, posterior cruciate ligament tear in 5, medial collateral ligament tears in 11, lateral collateral ligament tears in 9 patients. The difference was significant (P< 0.05). Sensitivity of MRI was 100%, specificity was 85%, positive predictive value was 86.5%, negative predictive value was 100% and kappa was 0.85. Conclusion:Anterior and posterior cruciate ligament tears, chondromalacia patellae, rheumatoid arthritis, medial collateral ligament tears, lateral collateral ligament tears, medial meniscal tears, and lateral meniscal tears were among the frequent knee diseases. An accurate and reasonably priced radiographic tool for diagnosing sore knees is magnetic resonance imaging (MRI).