Thirteen patients with 14 large rotator cuff tears were operated on using carbon fiber to cover the defect. The median follow-up time was 4 years. In 11, 1, and 2 cases the results were respectively excellent or good, fair, and poor. In 2 cases where the carbon fiber was anchored to the major tuberosity, a bone cyst was seen, but it did not influence the result. A carbon fiber tow application combined with Neer's anterior acromioplasty seems useful in the reconstruction of large tears of the rotator cuff.