ObjectiveTo detect the content of stromal cell derived factor-1α(SDF-1α) in peripheral blood of patients with gastric adenocarcinoma (GC) and investigate its clinical significances. MethodsThe contents of SDF-1αin the peripheral blood of 90 patients with GC were detected by enzyme-linked immunosorbent assay. The correlation of SDF-1αcontent with the clinicopathologic parameters and prognosis after operation were analyzed. Results①The content of SDF-1αin the patients with GC[(6950.8±1131.3) ng/L] was significantly higher than that in the normal healthy volunteers[(5023.7±1103.8) ng/l, P=0.036].②The content of SDF-1αin the GC patients with distant metastasis[(8251.6±1042.5) ng/L] was significantly higher than that without distant metastasis[(6785.3±1025.0) ng/L, P < 0.001]. The contents of SDF-1αin the peripheral blood of patients with distant metastasis either in the liver (P=0.002) or in the lung (P=0.030) were significantly higher than those without distant metastasis (liver or lung).③The TNM stage was later (P < 0.001), lymph node metastasis was broader (P=0.018), invasion of tumor was deeper (P < 0.001), vascular invasion (P < 0.001) and lymphatic vessel invasion were present (P < 0.001), the contents of SDF-1αwere higer. Logistic regression analysis revealed that the depth of tumor invasion (OR=14.999, 95% CI 3.568-74.456, P=0.027) and distant metastasis (OR=0.186, 95% CI 0.610-2.014, P=0.026) were correlated with the high SDF-1αcontent.④The survival time of the patients with higher content of SDF-1αwas significantly shorter than that of the lower content of SDF-1α(P < 0.001). Cox proportial hazard regression model analysis demonstrated that TNM stage (RR=2.497, 95% CI 1.987-10.238, P=0.009), vascular invasion (RR=7.501, 95% CI 2.086-16.942, P=0.002), and high content of SDF-1α(RR=18.302, 95% CI 6.895-30.538, P=0.001) in the peripheral blood were the independent risk factors for survival of the patients with GC. ConclusionHigh content of SDF-1αin peripheral blood might suggest the occurrence of lymph node metastasis, hepatic metastasis or lung metastasis and indicate the poorer prognosis of GC.