It is the universality principle of human rights,the purpose of the establishment of the self-defense system, and the objective needs of juridical practice that determines the legitimacy of the existence of the inverse denfense. As a special case of self-defense,the conditions of the inverse defense, such as the premise condition, subjective condition, limitation of constitution ,and so on, are different from those of the justifiable defense;Juridicus are asked more restrictive to identify and deal with the inverse defense in juridical practice.