We experienced a case of glenohumeral osteoarthritis following arthroscopic Bankart repair. A 22-year old man came to our hospital with a complaint of recurrent anterior subluxation of his left shoulder. He received arthroscopic Bankart repair using 5 absorbable suture anchors and 2 Fiberwires on each anchor and started ROM exercise after 3 weeks immobilization. At 18 months after the surgery, X-rays, CT and MRI exhibited joint space narrowing, spur formation and cystic lesion, indicating glenohumeral joint osteoarthritis. At 32 months after the surgery, arthroscopic exmination indicated that abrasion powders of the Fiberwires were observed in the cystic lesion of the joint, and arthroscopical intervention was performed including resection of the powders and curettage of the cyst. At 6 months after the repeat surgery, this patient complained of no symptoms and his shoulder had good stability. CT also demonstrated the cystic lesion had improved. In this case, the abrasion powder of Fiberwire suture might have induced inflammatory arthritis, subsequently become osteoarthritis, since the powders were observed in the cystic lesion and resection of the powders improved the cystic lesion. Previous papers have reported that the bioabsorbable anchor caused osteolysis and arthropathy, but there have been no studies that show Fiberwire suture alone caused osteoarthritis. Our case suggested that Fiberwire suture also might cause osteoarthritis. We reported a case of glenohumeral osteoarthritis following arthroscopic Bankart repair. The abrasion powders of Fiberwires might cause osteoarthritis.