Objective To discuss the value of magnetic resonance imaging (MRI) and multislice spiral CT (MSCT) in the diagnosis ofpreoperative N staging and lymph node metastasis of gastric cancer. Methods The clinical data of 39 patients with gastric cancer examined by MRI and MSCT before operation were retrospectively analyzed. With postoperative pathological resultsas the golden standard, the value of MRI and MSCT in the diagnosis of lymph node metastasis of gastric cancer was analyzed. The imaging features of metastatic lymph nodes and non-metastatic lymph nodes were compared. Results The accuracy, total accuracy and Kappa valueof MRI in the diagnosis ofN1, N2, N3a and N3b stages of gastric cancer were 66.67%, 88.89%, 70.00%, 57.14%, 71.79% and 0.609 respectively, while those of MSCTwere 33.33%, 66.67%, 90.00%, 71.43%, 76.92% and 0.621 respectively.There was no statistically significant difference in the diagnostic accuracy between the two methods(P>0.05), and both of them were in good consistencywith the postoperative pathological results. There were no statistically significant differences in the short diameter or the long diameter between metastatic lymph nodes and non-metastatic lymph nodes diagnosed by MRI or MSCT (P>0.05), and the rADC value of metastatic lymph nodes was significantly lower than that of non-metastatic lymph nodes (P<0.05), and the degree of enhancement was significantly higher than that of non-metastatic lymph nodes (P<0.05). Conclusion Both MRI and MSCT are of high diagnostic value for preoperative N staging of gastric cancer. The rADC value in DWI and the enhancement degree of MSCT can be used asimportant indexes to determine the properties of lymph nodes.