A desmoid tumor is a locally aggressive growth of connective tissue origin which infiltrates the surrounding tissue and has a marked tendency for recurrence. And so it was also called as an aggressive fibromatosis, musculofascial fibromatosis or fibrosarcoma etc. Thirteen cases of desmoid tumor was treated since 1980, and their retrospective study was done with 79 months of follow-up after initial surgical excision. The female was involved in 12 cases(one male) with the age ranged from 7-50 years, average 28 years, and seven patients in third decade. A slowly growing mass was excised on average 4 months after first notice of the mass, but their margins are not demarcated clearly in most cases. Wide excision in 12 cases was done, but wide excision and saphenous vein graft was performed in one case because of invasion of posterior tibial artery by tumor mass. The tumor was found on extraabdominal region in 8 cases(61.5%) but 5 cases in abdominal wall(38.5%). The recurrence rate was high(6/13, 46.2%), and 11 times in 6 patients were recurred(average 1.8 times), within 27 months of initial excision. Six cases of recurrence were treated with wide excision again in 3 cases, wide excision combined with radiotherapy(4,000-6,000cGy) in 4 cases and wide excision with chemotherapy in one case. During the follow-up for average 21 months after treatment, no recurrences are found. Tumor remission periods without recurrence are average 67 months in all, and 11 years in longest case. Histologically it was very mimic with fibrosarcoma but could be differentiated with Trichrome stain, and their findings are not changed after recurrence.