Preoperative serum levels of sialyl Lewis(a) (CA19-9), sialyl Lewis(x) (SLX) and sialyl Tn (STN) antigens in 180 patients with gastric cancer were examined to establish predictive factors for serum levels of these antigens compared with carcinoembryonic antigen (CEA). The patients were divided into low and high antigen groups. Multivariate logistic regression analysis revealed the following independent predictive factors for high antigen levels [odds ratio]: liver metastasis for CA19-9 [4.40], SLX [9.90], STN [39.65] and CEA [5.14]; peritoneal dissemination for SLX [4.78] or STN [13.01]; venous invasion for CEA [3.56]; lymph node metastasis for CA19-9 [4.51]. In addition, high CA19-9 levels were independently related to lymph node metastasis in patients with stage I or II tumors. In conclusion, high serum levels of CA19-9, SLX and STN are associated with liver metastasis, while high serum levels of SLX and STN are associated with peritoneal dissemination. In addition, high serum CA19-9 levels may represent an independent predictor for lymph node metastasis.