Anatomically flexor pollicis longus is different from deep finger flexors. Flexor pollicis longus tendon is unique in that it may be advanced without disturbing its blood supply, since it has no vinculum. From January 1990 to December 1992, 17 cases of patients with laceration of the flexor pollicis longus tendon were treated at Kyungpook National University Hospital. The follow up period ranged from 3 to 36 months. The results were as follows; 1. agents causing the laceration were broken bottles in 10 cases(58.8%), knives in 3 cases(17.6%) and machinary like saw in 2 cases(11.8%). 2. Totally 17 cases, 9 cases of them were located at distal to metacarpophalageal joint. 3. As associated injuries, digital nerve injuries were 4 cases(23.5%) and the recurrent branch of median nerve injuries was 1 case. 4. The surgical treatment was direct suture with or without proximal lengthening in 13 cases(76%) as primary or secondary repair and distal advancement with or without proximal lengthening in 4 cases(24%) as secondary repair. 5. Distal to metacarpophalangeal joint, the surgical treatment was direct suture with or without proximal lengthening in 3 cases as primary or secondary repair and distal advancement with or without proximal lengthening in 4 cases as secondary repair. 6. The result by Urbaniak method was excellent in 8 cases(47.0%), good in 7 cases(41.2%) and fair in 2 cases(11.8%). 7. Based on the results in these patients, it was recommended that secondary treatment for lacerations distal to the metacarpophalangeal at the wrist, as needed is bettewr than free tendon graft.