To study the clinical diagnostic value of treating gastric cancer (GC) with combined tests for tumor markers (CEA, CA199, CA242 and CA724), fifty healthy subjects, 50 patients with GC at different stages and 50 patients with benign GC were randomly selected from our hospital. These subjects were divided into a normal group A, an experimental group B and a control group C. Venous blood was drawn and tested for four serum tumor markers. The SPSS 18.0 analytic system was then used to analyze the data. Tumor markers for GC at different stages, different pathological patterns and tumor incidence are discussed. The difference in expression levels of tumor markers between group C and group A was not statistically significant (P>0.05). The differences in expression levels between group B in stage I and stage II and those of groups A and C was statistically significant (P less than 0.05). At the same time, the differences in expression levels of group B in stage III and stage IV and those of groups A and C were also statistically significant (P less than 0.01). For different sizes of tumors, taking 5 cm as a maximum, normal expression and abnormal expression of the four tumor markers was different (P less than 0.05). The tumor incidence of the combined test for the four tumor markers was conspicuously higher than that of single tests. Moreover, the difference between the tumor incidence of the combined test in stages I, II and III and that of single tests in the same stages was of statistical significance (P less than 0.05); however, the difference was not statistically significant in stage IV (P>0.05). The combined testing for tumor markers is useful for clinical diagnosis of GC.