Objective To explore the effectiveness of modified percutaneous mini-incision Achilles tendon lengthening for the treatment of Achilles contracture syndrome by comparing with traditional open Achilles tendon lengthening. Methods Between May 2008 and May 2012, 42 patients with Achilles contracture syndrome were treated and the clinical data were retrospectively analyzed according to the inclusion criteria. The modified percutaneous mini-incision Achilles tendon lengthening was used in 19 cases (19 feet, trial group); 0.5 cm incisions were designed at medial and lateral Achilles tendon according to the degree of Achilles contracture syndrome; and percutaneous double hemi-section was done according to the deformity range of varus and valgus foot. The traditional open Achilles tendon lengthening was used in 23 cases (24 feet, control group). There was no significant difference in age, gender, disease duration, motion of ankle dorsiflexion, and Hannover Achilles tendon score (P gt; 0.05). Results The operation time, postoperative hospitalization days, and intraoperative blood loss in the trial group were less than those in the control group, showing significant differences (P lt; 0.05). After operation, incision healing by first intention was obtained in the other cases except 1 case which had infection in the control group. The patients were followed up 6-35 months in the trial group and 8-34 months in the control group. Correction of varus deformity foot was not obvious in 1 case of the trial group, correction of varus and valgus deformity feet were satisfactory in the other cases. There was no significant difference in motion of ankle dorsiflexion and Hannover Achilles tendon score between 2 groups at last follow-up (P gt; 0.05), but significant differences were found between preoperation and last follow-up in 2 groups (P lt; 0.05). There were significant differences in motion of ankle dorsiflexion and Hannover Achilles tendon score between normal and affected sides in 2 groups at last follow-up (P lt; 0.05). Conclusion Modified percutaneous mini-incision Achilles tendon lengthening has similar effectiveness to the traditional open Achilles tendon lengthening for Achilles tendon contracture syndrome. And it can effectively correct varus and valgus deformities of the foot with less trauma and fast recovery.