Desmoid tumors are histologically defined as fibromatosis occuring in the musculoaponeurotic soft tissue. They rarely metastasize, but often behave as malignant tumors in the clinical setting because of frequent recurrence and local invasion. Desmoids occur more commonly in association with familial adenomatous polyposis (FAP) than with any other disease, ranging in frequency from 4% to 13% in patients with FAP. In patients with FAP, desmoids often appear after total colectomy as descrete masses in surgical scars of the abdominal wall or as infiltrating fibroblast sheets within the abdominal mesentery or retroperitoneum. Intra-abdominal or mesenteric desmoids pose a serious management problem because of their propensity to surround and compress major blood vessels and viscera. Recently we experienced a ease of desmoid tumor associated with FAP after tatal colectomy. This is the first case in Korea and thus, we report it with review of the literatures.