Objective To evaluate the role of preoperative 64 multi-detector spiral CT (MDCT) in predicting the extent of radical resection for advanced gastric cancer (AGC)． MethodsThe imaging data of 70 patients with AGC were collected and analyzed. The N2 lymph node metastasis was predicted by the MDCT indications, and compared with that postoperative pathological results. Results Sixty-two patients were treated with surgical intervention. The sensitivity, specificity, and accuracy of N2 positive prediction by MDCT was 92.0% (46/50), 75.0% (9/12) and 88.7% (55/62), respectively. Extended resection was performed in 81.6% (40/49) patients who were predicted as N2 positive, and D2 resection was performed in 92.3% (12/13) patients who were predicted as N2 negative.Conclusion The MDCT is a valuable technique to predict N2 lymph node metastasis, and to determine the extent of resection for AGC.