The present investigation is born from a serious context of violence and discrimination against women in Peru, becoming one of the main social problems that we have to face at present, also it is oriented to establish the unconstitutionality of the crime of Feminicide, recently incorporated into the Peruvian penal code (Art.108-B), with the aim of building truly effective public policies. In order to do so, the scopes, definitions, characteristics and functionality of each constitutional principle (legality, culpability and equality) have been delimited in the first place. Subsequently, the nature of the criminal offense was studied, together with its constitutive circumstances, and the whole body of criminal legislation in force was analyzed, including Law No. 30364: "Law to prevent, punish and eradicate violence against women and the members of the family group ''. Once each concept de...