Pain snd disability often fractures of the cslcaneus even though the original injury was skillfully treated. The causes are traumstic arthritis of the subtalar joint, abnormalities of the peroneal tendons or weakness of Gastrocnemius, etc. We have experienced the resection of lateral prominence of calcaneus in 7 patients who complained of pain by entrapment of peroneal tendons between lateral malleolus and lateral prominence of malunited calcaneus. The follow up time after operation was 3 years and 4 months to 12 months. In all patients the pain was markedly improved between postoperative 5 weeks and 10 weeks. When the last follow up, 6 patients among 7 patients except one case of subtalar arthritis were astisfaetory.