Abstract: Objective: To explore the value of multi-slice spiral computed tomography(MSCT) in the diagnosis of gastric cancer.Methods: Twenty-six cases of plain CT,enhancement CT scanning and multiplanar reconstruction after the stomach becomes low tense and full of water contrast with the results of gastroscope and operation pathology.Results: The rate of MSCT examination about the advancing gastric carcinoma was 100.00% and it achieved 96.15%(25/26) to make a definite diagnosis enhancement CT scan was better than any other ways in diagnosing the TNM-classification of gastric carcinoma.Conclusions: The value of MSCT in examing gastroma is very high and enhancement MSCT scan is the best way in the definite of TNM-classification in gastric carcinoma before operation.