<;P>;PROBLEM TO BE SOLVED: To obtain a composition for preventing a pathological condition caused by immune regulation abnormality and ameliorating a symptom. <;P>;SOLUTION: The oral immunomodulator is obtained by formulating a milk obtained by hyperimmunizing a milking animal with an immunogenic substance and milking the animal or a composition prepared from the milk, which contains an IgG to specifically recognize the immunogenic substance with an antibody target substance to be specifically recognized by the IgG and is orally administered. The oral immunomodulator is preferably used for preventing an allergic disease and a rheumatic disease and ameliorating its symptom. <;P>;COPYRIGHT: (C)2008,JPO&INPIT