Purpose: The purpose of this study was to evaluate the effects of muscle strengthening exercise on shoulder function and pain for rotator cuff tear patients. Method: The subjects of this study, partial tear of the rotator cuff diagnosed patients, twelve patients were picked up, who were agreed with this research. The twelve patients received muscle strengthening exercise for 4 weeks, which consisted of 5 times per week, 40 min of supervised exercise program. Shoulder function and pain, measured by ROM, CMS, SST, PPT and VAS. Result: In comparison of VAS, PPT and ROM, CMS, SST were showed a more improved after intervention. Conclusion: Therefore, muscle strengthening exercise is useful to improve the shoulder function and pain for rotator cuff tear patients.