Abstract The current investigation focused on lymphoid cell populations of adult male Sprague-Dawley rats fed a total enteral nutrition diet in which ethanol provided 38% of the total calories. Rats received the National Research Council (NRC) recommended daily intake of nutrients 35 days. An evaluation of lymphocyte populations from peripheral blood demonstrated a decrease in the absolute number of B cells ( p ≤ 0.007) and absolute numbers of CD4 T cells ( p ≤ 0.06) in the ethanol-treated animals. Spleen and thymus weights were significantly reduced ( p = 0.0001) in the ethanol-treated rats and the CD4 CD8 ) ratio of splenic lymphocytes decreased in the ethanol group ( p ≤ 0.03). Thymus T-cell recovery from the ethanol-treated group was significantly reduced with no apparent redistribution in subset numbers with the exception of a minor, yet significant, decrease ( p ≤ 0.05) in the CD4 CD8 ratio. These data are the first to demonstrate that chronic alcohol intake alters lymphoid cell populations in the peripheral blood and primary organs of the immune systems in the presence of adequate nutrition.