ENThe subject of the present research is feudal Belarusian law at the stage of its unification into common land law. The research is aimed at investigating the evolution of basic legal institutes revealing their essence and regularities of development The author analyzes the tendencies which gave birth to the branch structure of law. To achieve this aims of research common scientific and special methods have been applied. The research has resulted in the complex analysis of the norms and institutes of civil and criminal law focusing on typical features, regularities and tendencies of their development The author shows the interrelation of the tendencies of law development with socio-economic processes in a feudal state. The problems of the sources of law has been further investigated. The research has filled in a gap in the history of law dealing with general theoretical problems of feudal law1 development and certain institutes of law. Such concepts reflecting the character and the tendencies of development of law of property as obligation, inheritance law and major institutes of criminal law has been introduced into scientific analysis. The author studies interrelation of the genesis of feudal Belarusian law with common European process of development and systematization of law. The results of the research have been used in teaching practice, in writing textbooks, in compiling encyclopedic commented edition of Statute of 1568, and can be used in compiling generalized works and textbooks on the history of state and law of Belarus, in the working out of a special course on comparative history of law and in the elaboration the conception of the development of law in feudal Belarus.