Ankle arthritis is one of the most disabling and painful conditions. Up to 37.5% of ankle arthritis presents as asymmetric arthritis with ankle malalignment. Supramalleolar osteotomy is a joint sparing operation, which aims to realign the ankle joint that will prevent progression of arthritis and relieve patient's symptoms.The aim of this study is to analyse the medium term functional and radiographic outcomes of patients who underwent supramalleolar osteotomy for asymmetric ankle arthritis.f medium term outcome for 33 patients who underwent Supramalleolar osteotomy for asymmetric ankle arthritis by a single surgeon. We assessed the functional outcome of the patients with AOFAS and VAS score. The radiological parameters measured were Tibial articular surface ankle (TAS), Hind foot alignment angle (HFA) and Talar tilt angle (TT). We used the paired Student's -test to compare the preoperative and postoperative radiographic measurements, AOFAS and VAS scores. We set the significance level at P < 0.05.We had 21 patients who underwent lateral closing wedge osteotomy for varus deformity and 12 patients who underwent medial closing wedge osteotomy for valgus deformity. The mean followup was 72 months [29-73]. The mean AOFAS score significantly improved by 44.82 ± 7.97 (p < 0.0001). The VAS score significantly improved by 5.06 ± 1.41 (p < 0.0001). All the radiological parameters showed statistically significant improvement. All osteotomy united by 8-10 weeks. We had one case of late deep wound infection, which settled down with by metalwork removal. The arthritis progressed in three cases, two patients had fusion and one patient had ankle replacement. We had 90.9% survival rate for our osteotomy at 6 years.Supramalleolar osteotomy is an excellent option for patients with asymmetric ankle arthritis with good functional and radiological outcome and good medium term survival rate.