T The Flexor tendon injury caused by trauma of hand and forearm is commonly reported and earlier treatment for trauma is recommendable. But in many cases, earlier treatment is often not possible due to degree of injured tissues and infection. Specially in cases of severe trauma and damage of tendon sheath and pulley, the solution of limitation of motion is still remained as a difficult problem up to present due to scar tissue adhesion to surrounding tissues even after the primary treatment. The Department of orthopaedic surgery of National Medical Center during four years from 1981 to 1985 have treated 22 patients (27 fingers) of old flexor tendon injuries with tendon reconstruction and followed up more than for 6 months for clinieal study arrd the results ase as follows: 1. The old flexor tendon injuries are composed of 18 patients of the first decade and the second decade, especially in male. 2. The main causes of injury were deep lacerations by sharp objects (12 patients, 55.6%) and crushing injuries (9 patients, 40.8%). 3. Tendon injuries were mostly occurred in the index and ring finger. The incidence rate was equal between the 2 fingers, 25.7% representatively. Most of the injuries (21 cases, 77.8%) occurred in the zone II (Kleinert classification). 4. According to Boyes’ classification, Grade 2 was 16 patients (19 cases): Grade 4, 3 patients (4 cases): Grade 3, 2 patients (3 cases): and Grade 5, 1 patient. 5. The operation method in zone II was free tendon graft in 10 cases and staged tendon graft in 7 cases. 6. The timing of operation depends on whether the open wounds were completely healed or not as well as subsidence of swelling. In case of swelling. In case of stiff fingers normal range of motions should be restored by vigorous exercise before operation. 7. According to the assessment based on strickland and Glovac, 20 cases out of 22 cases (13 cases of free tendon graft and 9 cases of staged tendon graft were satisfactory result.