Nerve compression of the suprascapular nerve by a suprascapular notch occasionally occurs, but comperssion by a ganglion is very rare. We had experienced a case of compression of the suprascapular nerve by ganglionic cyst at the suprascapular notch, which confirmed by electromyographic studies after the diagnosis was suspected. MRI scan showed multiobulated cyst at the right suprascapular notch. The patient was treated by excision of the ganglion and had excellent result.