Background: This study was performed to verify reports of the degreased accuracy of endorectal ultrasonography (EUS) in preoperative staging of rectal cancer. Methods: One hundred and fourteen consecutive rectal cancer patients undergoing curative surgery were evaluated by 3 D EUS preoperatively. Results: The overall accuracy in T-staging was 86, 8%, in there the accuracy in T2-staging was 83, 3%, in T3 was 89, 2% and in T4 was only 71, 4%.