Purpose: The purpose of this study is to describe the characteristic clinical findings and treatment of suprascapular nerve entrapment by ganglion and to evaluate its results. Materials and Methods: Seven paitents with suprascapular nerve entrapment were evaluated on an average 13 months(range, six months to three years two months) after surgical excision and decompression. There were six males and one female. The mean age at operation was 31 years(range, 23 to 40 years), Suprascapular nerve entrapment were caused by compression of ganglion cyst in suprascapular notch or spinoglenoid notch in all cases. All patients complained of pain located over posterolateral area of the shoulder. Two patients had atrophy of both the supraspinatus and infraspinatus muscles, In four patients, only the infraspinatus muscle was involved. Muscle strength on both forward flexion and external rotation was decreased in two patients. In four patients, only external rotation was decreased. All patients underwent open excision of ganglion cyst and decompression. Results: The most dramatic effect of operation was prompt disappearance of pain in all patients. The average visual analog scale had improved from 7.2 to 0.6 point at the latest follow-up evaluation. An atrophy of the supraspinatus or infraspinatus muscle partially disappeared in four of six patients and muscle strength of forward flexion or abduction improved in all of six patients. The overall result was excellent for five patients and good for two. Conclusion: Surpascapular nerve entrapment by ganglionic cyst had clinically unique symptoms and signs on physical examination. Surgical excision is effective for symptomatic and functional outcomes. We believe that early intervention can be one of treatment modality before an irreversible damage occurs if the ganglion is large enough to compress suprascapular nerve, and to develop severe pain and muscular atrophy.