Objective:To investigate the relationship between coagulation function,platelet(PLT)counting and tumor infiltration,the clinical stage and metastasis status in gastric cancer patients. Methods:A total of 229 patients with gastric cancer were included in the study,with 53 cases in stageⅠof TNM classification,45 cases in stage Ⅱ,116 cases in stage Ⅲ,15 cases in stage Ⅳ. According the depth of tumor infiltration,there were 36 cases of early gastric cancer and 193 cases of advanced gastric cancer .There were 73 cases without metastasis and 156 cases with metastasis. Fifty heathy volunteers were set as the control group. The prothrombin time(PT),activated partial thromboplastin time(APTT),thrombin time(TT),fibrinogen(FIB),antithrombase(AT)-Ⅲ and PLT were detected. Results:FIB,AT-Ⅲ and PLT were significantly higher in the group with gastric cancer than in the control group(P < 0.05 or P < 0.01). Along with the progression of tumor infiltration,the Levels of FIB and PLT became gradually higher. PT were obviously shorten in gastric cancer patients without metastasis than in control group(P < 0.05). FIB and PLT were significantly higher in group with metastasis than in group without metastasis and the normal group(P < 0.01). Conclusion:The patients with gastric cancer are usually accompanied with disorder of coagulation and fibrinolytic systems. FIB and PLT significantly increasing associated with tumor infiltration,lymphatic and distal metastasis of cancer cells. Therefore,monitoring the coagulation indexes could be a useful way to diagnose and predict clinical stage of gastric cancer.