Objective To study the ultrastructural features of initial lymphatics of gastric carcinoma,to discuss the metastasis mechanism of malignant cells by lpmphatics. Methods The postoperative samples of patients with gastric cancer were obtained in center,peripheral and normal region of cancer.Common Resin-embedded specimens were made.Lymphatics were located by hemithin sections under light microscope and observed by ultrathin sections under electron microscope. Results There were no lymphatics in carcinomatous centre region.Compared with normal region,there were more initial lymphatics in peripheral region of gastric carcinoma.The lumina were dilated and irregular and the endothelium were destroyed;The organelle of endothelial cells changed obviously.The distribution and morphology of the lymphatics did not changed evidently in the normal region.Conclusion These results suggest that amount,ultrastructure and morphology of lymphatics changed in peripheral region of carcinoma;Gastric cancer cells may invade lymphatics via destroyed parts of endothelium or interendothelial openings.