Fundamental principles of criminal law theory lack a normative-structural analysis. Atienza´s and Ruiz Manero´s proposal in regards to legal decisions contain a typology of mandatory norms (rules, principles in a broad sense and directives) that is especially suitable for an analytical reconstruction of principles of criminal law. This proposal is also relevant and useful in the field of constitutional courts' decisions related to Criminal law, because the principle or test of proportionality in its strict sense classifies fundamental rights into rules and principles. My aim in this paper is to discuss and propose a groundwork for normative reconstruction of the principles of criminal law using Atienza's and Ruiz Manero's framework.