The article discusses the legal and ethical aspects of loyalty as one of the foundations of state service in the Russian Federation, which is enshrined in the regulations of some foreign countries and, currently, is not reflected in Russian legislation. The study of foreign experience of legal regulation and organization of public service allows to draw a conclusion on the necessity of the principle of loyalty of the civil servant, incorporating it into the Russian legislation. The Authors substantiate the idea that the specificity of modern social relations, their dynamics, require the introduction of the principle of loyalty in the scientific revolution, the normative legal acts regulating the activities of state servants in Russia. According to the Authors, very important are legal and institutional aspects of the stimulation of the loyalty of the Russian civil servant.