The purpose of the research is to reveal the relationship between legal progress and the fundamental principles of law in the context of their implementation at different levels of the legal system. The importance of justice, freedom, equality and humanity as an instrument of legal progress is shown. It is proved that the fundamental principles of law act as the limits of the development of the legal system, and these limits ensure the legal and political progress of mankind. The methodological basis of the research is presented as comparative-legal and systematic analysis, formal-legal method, method of interpretation, hermeneutic method, as well as methods of analysis and synthesis. In the conclusions the authors state that legal progress depends on the extent to which the fundamental principles of law are presented and implemented in the actual legal order. The fundamental principles of law converge with each other. Thus, it can be said that it is precisely the interaction and synergy of principles that strengthens legal progress in a given society.