We performed 15 cases of modified Bristow procedures for recurrent anterior instability of shoulder from january, 1987 to december, 1992 and the following results were obtained. 1. The patient's age at initial dislocation varied from 15 years to 29 years of age. 2. The most common cause of the recurrent anterior instability of shoulder was sport injury(6 cases) and next were traffic accident, hanging with one hand. 3. The average loss of external rotation of shoulder after operation were 10 degrees and internal rotation were 7 degrees. 4. The post-operative complication and recurrence were not observed. 5. End results were excellent in 7 and good in 5 by Rowe's grading system. 6. Strict attention to bone block placement was mandatory and decreased the risk of screw malpo-sition.