Abstract: The identification of unlawful infringement is closely related to the original purpose of the establishment of the right of defense, and unlawful infringement should be identified for the purpose of protecting the legal rights of citizens. As the premise of launching the right of defense, the identification of unlawful infringement should be based on the infringement of legal interests, rely on the contempt for rights, and take the maintenance of social unity as the limit. In other words, the infringement of legal interests should be the starting point for identification, and unlawful infringement should be limited to infringement under the control of subjective will with the help of the jurisprudence of right infringement and social solidarity. When identifying unlawful infringement, we should adhere to the distinction between the establishment premise and exercise conditions of the right of defense, taking the awareness of the perpetrator at the time of the act as the yardstick, taking the empirical evaluation as the basic basis, insisting on the principle of social solidarity, to balance the relationship between the interests protected by defense and the social public interests from the perspective of the maintenance of social interests. According to the destructiveness of the infringing act, the rules of unlawfulness and the difficulty of recovering the result of the damage caused, some acts with infringement of legal interests and contempt for rights are excluded from the scope of unlawful infringement.