Abstract: This paper reports the relation between the macrophage phagocytosis (Mp) and esophageal cancer (EC) found through the in vitro test of chicken red cells swallowed by the macrophages that were obtained from skin blistering arising from the cantherides alcohol infusion. Test results showed that gradual decrease (P0.001) of MP was seen in 48 volunteers with normal esophageal epithelium, 20 subjects with mild dysplastic epithelium, 29 subjects with severe dysplastic epithelium and 4 EC patients from the suburbs of He Bi City, an EC high incidence area in Henan; and that the MP of 37 EC patients of Henan Tumour Hospital was lower than MP of 20 healthy normal subjects (P0.001) flying in Zhengzhon. These results suggest that the lowering of MP may be one of the contributing factors in the incidence of EC. Thus one of the important measures for the prevention of this malignant tumour lies in making efforts to raise the MP of the body.