Objective To evaluate the effectiveness of flexor hallucis longus tendon harvested using a minimally invasive technique in reconstruction of chronic Achilles tendon rupture. Methods Between July 2006 and December 2009, 22 patients (22 feet) with chronic Achilles tendon rupture were treated, including 16 males and 6 females with a median age of 48 years (range, 28-65 years). The disease duration was 27-1 025 days (median, 51 days). Twenty-one patients had hoofl ikemovement’s history and 1 patient had no obvious inducement. The result of Thompson test was positive in 22 cases. The score was 53.04 ± 6.75 according to American Orthopedic Foot and Ankle Society (AOFAS) ankle and hindfoot score system. MRI indicated that the gap of the chronic Achilles tendon rupture was 4.2-8.0 cm. A 3 cm-long incision was made vertically in the plantar aspect of the midfoot and a 1 cm-long transverse incision was made in a plantar flexor crease at the base of the great toe to harvest flexor hallucis longus tendon. The flexor hallucis longus tendon was 10.5-13.5 cm longer from tuber calcanei to the end of the Achilles tendon, and then the tendon was fixed to the tuber calcanei using interface screws or anchor nail after they were woven to form reflexed 3-bundle and sutured. Results Wound healed by first intention in all patients and no early compl ication occurred. Twenty-two patients were followed up 12-42 months (mean, 16.7 months). At 12 months after operation, The AOFAS ankle and hindfoot score was 92.98 ± 5.72, showing significant difference when compared with that before operation (t= —40.903, P=0.000). The results were excellent in 18 cases, good in 2 cases, and fair in 2 cases with an excellent and good rate of 90.9%. No sural nerve injury, posterior tibial nerve injury, plantar painful scar, medial plantar nerve injury, and lateral plantar nerve injury occurred. Conclusion Chronic Achilles tendon rupture reconstruction with flexor hallucis longus tendon harvested using a minimally invasive technique offers a desirable outcome in operative recovery, tendon fixation, and complications.