Abstract: Objective To elucidate the association between expression of MUC1 gene in the tissues of gastric carcinoma and intestinal metaplastia and its clinicopathological factors. Methods MUC1 core protein was detected in the normal gastrointestinal mucosa and tissues of intestinal metaplasia and gastric carcinoma with BC2 antibody by immunohistochemical SP method.Reaults MUC1 core protein was diffusely distributed in human normal gastric mucosa(100%),mainly located in the perinuclear area of epithelial cells and cytoplasm of mucous neck cells and basal glandulae,the positive rates of core protein in the tissues of intestinal metaplasia and gastric carcinoma were 79.3%,82.6% respectively.No association was found between the expression of MUC1 gene in the cancerous tissues and the patients'sexes,locations and size of cancerous tissues,metastases of lymph node,types of differentiation,depth of invasiveness,clinical stages and lauren's types(P>0.05).But,the number of clinical stages Ⅰ～Ⅱ was significantly lower in those patients whose cancerous tissues were strongly positive staining than those with moderately and weakly posivive staining (P<0.05),No difference was found between expression of MUC1 gene and different types of intestinal metaplasia (P>0.05). Conclusion These results indicated that MUC1 core protein detected by BC2 antibody might be a useful marker for the progression of gastric carcinoma and associated with its clinicopathological factors,but no association with types of intestinal metaplasia.