Objective To study the MR characterizations of supraspinatus and infraspinatus tendon lesions by comparing with gross anatomy and histopathology. Methods The study group consisted of 20 cadaver shoulders which were underwent the same imaging protocols of conventional MRI and MR arthrography. Results SE-T2WI images or MR arthrography respectively possessed of high specificity (95.6%, 100%), but low sensitivity (70.6%, 58.8%) for diagnosing rotator cuff tears. By uniting two images techniques, could remedy its limitations and would markedly increase the sensitivity (88.2%). There were many factors influencing the visualizations of partial thickness tears of rotator cuff on MR images, from which uppermost factors are tear extent, ruptured synovial capsule, scar and synovial proliferation. Conclusion MRI diagnoses of rotator cuff lesions (especially partial thickness tears) must carefully be estimated by combining T2WI images and MR arthrography.