The aim of this paper is to outline the general oversight of the concept of law in Leon Petrażycki’s legal theory. On the example of the principles of law, an attempt was made to answer the question, what Petrażycki’s theory proposes to modern science. In the first part of the presentation, the Author presented the current state of theoretical knowledge in the field of principles of law. The attention was paid to the problem of various characteristics of legal principles. In (...) further considerations, an attempt was made to answer the question about adoption of models proposed by Petrażycki in the contemporary theoretical discourse. The summary presents general conclusions of the paper. (shrink)