ObjectiveTo assess the clinical prognostic value of the 7th edition TNM staging system for gastric cancer patients after operation. MethodsThe clinical data of 381 gastric cancer patients who received operation in Changhai Hospital during 2002 to 2005 were retrospectively analyzed. And the patients were staged using the 6th and 7th edition of TNM staging system separately. The survival curves of different patients were compared. ResultsThe changes of survival curves were significantly different between different T and N classifications of the 7th edition of TNM staging system (P<0.05). The changes of survival curves were significantly different in patients with different T2 and T3 classifications and different N1 and N2 classifications in the 7th edition (P<0.05). The survival rate of Ⅳ stage patients in the 6th edition, whose stage was down-regulated in the 7th edition, was significantly higher than those of patients whose stages were not down-regulated in the 7th edition (P<0.05). ConclusionThe 7th edition provides a more detailed and more rational staging for gastric cancer patients than the 6th edition, especially for the T and N staging classification. The 7th edition also has a more accurate prognostic value for gastric cancer patients.