Abstract: Objective :To explore the effect of Highly Agglutinative Staphylococcin (HAS) on an-ti-neoplastic activity of tumor-draining lymph node (TDLN) cells in patients with gastric carcinoma. Methods :Forty patients with gastric carcinoma were randomized into the experimental group (HASgroup) and the controls. The patients in the experimental group were injected with HAS for 7 successivedays before surgery. The TDLN were removed from patients during the operation. TDLN cells were iso-lated and purified from local lymph nodes of the patients. The cytotoxic activity of TDLN cells to gastricadenocarcinoma cell line KATO3 and the human melanoma cell line A375 were compared in the twogroups. Results :The cytotoxicity of TDLN cells to KATO3 cells in the experimental group was signifi-cantly stronger than that of TDLN cells in the control group. In contrast, for A375 cells, cytotoxic activ-ities of TDLN cells in the two groups showed no overt difference. Conclusion :The antineoplastic activ-ity of TDLN cells can be enhanced significantly by HAS.