The aim of the present study was to compare the accuracy of transrectal ultrasound in staging rectal carcinoma. 30 consecutive patients with rectal carcinoma proven pathomorphological were staged transrectal ultrasound and computed tomography imaging, and then underwent radical surgery. The data of preoperative staging were compared with pathomorphological findings of the specimens according to Surgical excised the TNM classification system. Transrectal ultrasound showed better results than computed tomography in evaluating N (sensitivity 45.2%, specificity 45.2%), because the parameters of sensitivity and specificity were high enough (76.6%). Computed tomography has limited usefulness in staging rectal tumors because the layers of the rectal wall are not resolved by computed tomography. In T staging transrectal ultrasound sensitivity and specificity ranges 87.54% and 94.82% respectively and that enables to perform adequate surgical procedure.