Abstract: Objective :To investigate the expressions of MUC1 in human carcinoma of bladder and cystitis glandularis and their significance. Methods :MUC1 was detected in 48 cases of bladder carcinoma (tumor group), in 45 cases of cystitis grandularis (benign group) and in 10 cases of human normal bladder (control group) with immunohistochemical stains and HMIAS -2000 image analysis system. Results : The mean value of gray scale for MUC1 was significantly lower in tumor group and benign group, compared to control group (P<0.01). Furthermc) the value was significantly lower in tumor group than in benign group, but there was no significant difference between the two (P>0.05). Conclusions :As a new tumor-associated antigen, MUC1 may play an important role in the occurrence and progress of bladder carcinoma and can also be used for immunotherapy.