Disclosed is an antibody produced using an ostrich. Also disclosed is a method for producing the antibody. By using an ostrich, it becomes possible to produce antibodies (particularly antibodies for medical use), which have been hardly produced by using the mammals such as the mouse and the rat, homogeneously in a single body, in large quantities and in a simple manner. The method can overcome a disadvantage of lot-to-lot variation which may occur in the production of polyclonal antibodies using other animals.