In Indonesia, arthrodesis becomes a choice of treatment in the absence of ankle arthroplasty implants for young adults. Arthrodesis on ankle osteoarthritis (OA) often leads to functional impairment. Low tibiofibular osteotomy is an alternative and it has been known to be the preferable option for those in the productive-ages. A 22-year-old male with a previous history of a motorbike accident, operated eight years ago, came with persistent pain on the left ankle that has worsened over the years. Plain radiography with a tibial-ankle surface angle (TAS) of 74o (normally 88o-93o) indicated varus deformity. Osteotomy was performed on distal tibia above the syndesmotic joint, as well as on the middle third of fibula. Open wedge osteotomy of the tibia was corrected until the normal TAS angle was reached by fluoroscopy. Cortical allograft was used to fill the osteotomy gap. Instrumentation was performed using a clover leaf® plate with 6 screws insertion for fixation stability. All results were satisfactory. Twelve weeks post-operatively, the patient was performing activities normally. Four-month post-operative radiological evaluation showed fusion of graft and the angle of TAS of 89°. Post-operative functional assessment using the American Academy of Orthopaedic Surgeon (AAOS) Foot and Ankle Measurement (FAM) questionnaires showed significant improvement (pre 89, post 38).