We had examined the levels of specific IgG and IgA to dietary antigens in human breast milk and the relationships between the maternal food intake and the specific antibody level. The highest antibody titers were found in colostrum and decreased as lactation progressed. The specific antibody level was not affected by maternal calorie or protein intake, but affected by the intake frequency of a kind of food. Egg and meat intake significantly related to anti-OVA IgG and anti-BSA IgA antibodies, respectively. Meat intake frequency was generally affected by the other specific antibody levels.