To define the effectiveness of surgical management of the mallet finger deformity due to extensor tendon injury in children, we analyzed 9 patients who had operative treatment of mallet finger deformity in children from Jan. 1994 to Mar. 1997. The types of tendon injury in this series were as follows: 7 cases with tendon laceration, 1 case with crushing injury and 1 case with unknown injury The average period of follow up were ranged 2 years and 1 month. The clinical results were evaluated hy Kanies seale12) and Crawford scale5). An excellent result was obtained in 4 cases(44%), a good result in 5 cases(56%) according to Crawford scale and excellnt result in 9 cases(I00%) in Kanies scale, consecutively. Meticulous surgical repair of the lacerated tendon provided good result.