Abstract: This study was aimed at investigating the effects of chronic alcohol consumption on immunochemistry of mice experimentally infected with E. coli strain 0157:H7. The bacterial organisms used were collected from an already identified and characterized stock (ECO 6) maintained for research purposes in the Laboratory of the Department of Veterinary Microbiology and Pathology, Faculty of Veterinary Medicine, University of Nigeria, Nsukka. About 1.15x104 CFU was used to challenge mice which were placed on prior treatment with various concentrations (10, 20, 30 and 40%) of ethanol for 3 weeks in separate groups, intraperitoneally. Blood samples were collected 7 days post bacterial challenge from the experimental mice via the retrobulbar plexus in the median canthus of the eyes. The samples collected into Bijou bottles were subjected to immunochemistry assay (hemagglutination test and Hemagglutination Inhibition (HI) test). The mean antibody titer in 40% alcohol-treated mice (341.33±85.33) was found to be significantly (p<0.05) lower than the value induced with 30% alcohol (512.00±0.00). The titer values however, produced with 20% (1024.00±0.00) and 10% alcohol (1706.70±341.33) were not only elevated but highly significant (p<0.01) compared to the alcohol effects at 30 or 40%, respectively. There was concentration dependent decrease in antibody titer induced with alcohol in the experimental mice. Low antibody titer correlates with decreased immune capability. Chronic exposure to alcohol could have depressed immunity due impaired cell proliferation in the hematopoietic tissues.