Objective To investigate the effectiveness of the free fibular skin flap of the great toe in repairing finger flexion deformity due to scar contracture. Methods The clinical data of 12 patients with finger flexion deformity due to scar contracture treated with scar release and free fibular skin flap of the great toe between March 2022 and December 2024 was retrospectively analyzed. All patients had flexion deformity caused by scar contracture of finger joints after healing of skin defect scar. The duration of scar contracture ranged from 3 months to 2 years, with an average of 7 months. The active range of motion of the finger joint was 0°-10°, with an average of 8°. The range of skin flap was 2.0 cm×1.3 cm to 3.5 cm×2.5 cm. Results All 12 patients were followed up 6-12 months, with an average of 10.5 months. At last follow-up, the flexion deformity of the affected finger was completely corrected, and the active range of motion of the finger joint was restored to close to the healthy side (the distal finger joint was 30°-40°, with an average of 35°; the proximal finger joint was 80°-90°, with an average of 85°). The shape of the flap was plump, the texture was good, and the static two-point discrimination was 6-8 mm, with an average of 6.8 mm. According to the evaluation standard of upper limb function of Chinese Medical Association Hand Surgery Society, 9 cases were excellent, 3 cases were good, and the excellent and good rate was 100%. All wounds at donor sites healed by first intention, with no pain, ulcer or ulceration in toes, normal walking in shoes, and no influence on gait. Conclusion Free fibular skin flap of the great toe is an effective method to repair the finger flexion deformity due to scar contracture, which providing good cosmetic, motor, and sensory outcomes with low donor-site morbidity.