Three strains of mice, BALB/c, IL-12 knock-out (KO) and INF-γ knock-out, were chosen as an experimental model for the study of intestinal immunity induction against Encephalitozoon cuniculi Levaditi, Nicolau et Schoen, 1923 infection. Mice were infected perorally with 107 spores and re-infected with the same dose 70 days after the first infection. The anti-E. cuniculi IgA, IgG and IgM responses in sera and extracts of stool samples were determined by ELISA. Results have shown specific antibody production in the sera and intestinal secretions of all three strains of mice induced orally by E. cuniculi spores. BALB/c mice developed a stronger humoral immune response than IL-12 KO mice. The lowest antibody response developed in INF-γ KO mice that succumbed to the infection within 28 days post infection.