Objective To determine the role of multimodal preoperative evaluation (MPE) system of transrectal ultrasound (TRUS), 64 multi-slice spiral computer tomography (MSCT) and serum amyloid A protein (SAA) in assessment of preoperative staging and selection of operative procedures of the lower and middle rectal cancer in multi-disciplinary team. Methods Prospectively enrolled 150 patients, who were diagnosed definitely as lower and middle rectal cancer (distance of tumor to the dentate line ≤10 cm) at West China Hospital of Sichuan University from November 2008 to March 2009, randomly assigned into two groups. In one group named MPE group, MPE consisting of TRUS, MSCT and SAA were made for the preoperative evaluation. In another group named MSCT+SAA group, both MSCT and SAA were made preoperatively. Then, the preoperative staging and predicted operative procedures were compared with postoperative pathologic staging and practical operative procedures, respectively. Furthermore, the pooled data were analyzed for the correlative relationship between the choice of surgery strategy and clinicopathological factors. Results According to the criteria, 146 patients with lower and middle rectal cancer were randomly assigned into MPE group (n=74) and MSCT+SAA group (n=72). The baselines characteristics of two groups were statistically identical. For MPE group the accuracy of preoperative staging T, N, M and TNM were 94.6% (70/74), 85.1% (63/74), 100% （74/74） and 82.4% (61/74), respectively; For MSCT+SAA group the corresponding rates were 77.8% (56/72), 84.7% (61/72), 100% （72/72） and 81.9% (59/72), respectively. The analysis showed a statistically difference in the accuracy of preoperative T staging between two groups (P=0.003) while there was no statistically significant difference of the accuracies of preoperative N, M and TNM staging between two groups (Pgt;0.05). There wasn’t a statistically significant increasing of the accuracy of prediction to operative procedures in MPE group compared with MSCT+SAA group 〔95.9% (71/74) vs.88.9% (64/72), P=0.106〕. When analyzing the relationship between multiple clinicopathologic factors and the operative procedures of lower and middle rectal cancer, there were statistical correlations between the pathological T staging (r=0.216， P=0.009), N staging (r=0.264， P=0.001), TNM staging (r=0.281， P=0.001), serum level of SAA before operation (r=0.252， P=0.002) or the distance of tumor to the dentate line (r=－0.261， P=0.001) and the operative procedures. Conclusion MPE system could display the accurate preoperative staging for lower and middle rectal cancer, on which the prediction of operative procedures can rest convincingly.