Computed tomography (CT) of ninety patients treated surgically for rectal cancer was reviewed to determine its value in investigating recurrence. The interval between operation and followup CT was within range of 1 month and 36 months. The final result of followup CT revealed fibrosis (41 cases) followed by true recurrence (37 cases) and not-proven cases (12 cases). The site of recurrence was presacral area (32 cases), pelvic side wall (15 cases0, lymph node (12 cases), liver (10 cases), bladder, uterus sacrum and others. CT is useful and noninvasive tool for assessing extension and postoperative staging of rectal cancer, but has limitation to differenctiate to recurred mass form fibrosis.