Objective To analyze the staging accuracy of spiral computed tomography (SCT) and magnetic resonance imaging (MRI) in preoperative tumor (T) and lymph node (N) staging of rectal cancer in comparison with postoperative pathological staging. Methods Eighty-six patients with histologically proven rectal carcinoma. 46 of the 86 patients were staged preoperatively using SCT, and the other 40 patients using MRI. According to the compared results, we discussed and evaluated the accuracy of SCT and MRI for preoperative staging in rectal cancer. Results The overall accuracy of SCT for T staging was 73.9%. By statistical analysis we found that the correlation was middling between preoperative SCT and pathologic T staging. We determined the values for accuracy of SCT in N staging was 62.5%, for sensitivity 87.5%, and for specificity 68.2%. By statistical analysis we found that the correlation was middling between preoperative SCT and pathologic N staging. The overall accuracy of MRI for T staging was 75.0%. By statistical analysis we found that the correlation was good between preoperative MRI and pathologic T staging. The values for accuracy of MRI in N staging was 62.5%, for sensitivity 85.7%, and for specificity 61.5%. And by statistical analysis we found that the correlation was middling between preoperative MRI and pathologic N staging. Conclusion Both preoperative SCT and MRI scans could provide good predicts compared to subsequent pathologic T staging. Furthermore, the accuracy of MRI ismuch better than that of the SCT. Both preoperative SCT and MRI scans provided poor predictive data.