Purpose : The purpose of this study was to evaluate the effects of early muscle strengthening exercise on pain, shoulder function and sleep quality for rotator cuff tear patients. Method : The subjects of this study, partial tear of the rotator cuff diagnosed patients, four patients were picked up, who were agreed with this research. This experiment is comprised two experimental groups, with two control groups. The experimental groups recieved early muscle strengthening exercise for 6 weeks, which consisted of 4 times per week, 40 min of supervised exercise program. The control groups received a general movement treatment of 6 weeks which consisted of 4 times per week, 40 min, Pain, shoulder function and sleep quality measured by VAS, PPT and ROM, CMS, SST and PSQI. Result : In comparison of VAS, PPT and CMS, SST and PSQI was the experimental group showed a more improved. Conclusion : Therefore, early muscle strengthening exercise is useful to improve the pain, shoulder function and sleep quality for rotator cuff tear patients.