PURPOSE: To evaluate the usefulness of early range of motion exercise by using 90degrees knee flexion splint after open reduction and internal fixation in fracture of distal femur. MATERIALS AND METHODS: We reviewed twenty-six cases of distal femur fractures which were treated with open reduction and internal fixation from February 2002 to November 2003. One group (group A) were treated by using 30degrees knee flexion splint, the other group (group B) were treated by using 90degrees flexion and full extension splint alternativley by post-operative 1 week. The follow up period was minimally 12 months. The range of motion and Schatzker and Lambert criteria were evaluated. RESULTS: The mean period to gain 90degrees knee flexion was 11.4 (7~14) weeks in group A, and 6.6 (3~8) weeks in group B. Mean range of motion was 94.7degrees (average flexion contracture 9.5degrees ) in A group and 108.7degrees (average flexion contracture 6.3degrees ) in B group at 12 weeks follow-up. According to Schatzker and Lambert criteria, excellent result was achieved in 10 cases (38%), good result in 13 cases (50%), fair result in 3 cases (12%). CONCLUSION: This study demonstrates that alternative splinting at extension and 90degrees flexion contribute to early recovery of range of motion in distal femur fractures treated with internal fixation.