The article presents the summary of the political psychology scientific research, fully corresponding to the academic traditions of the Department of Sociology and Psychology of Politics of Moscow State University. The study was devoted to a political and psychological analysis of the personality traits of populist-type politicians. The objectives of this study included psychological diagnosis and assessment of the personality of US President Donald Trump. A number of general scientific principles were used, including the principle of complexity, systematicity, subjectivity, integrability, reflexivity and optimality. The identification of basic psychological characteristics and the analysis of the most pronounced personality traits of Donald Trump were carried out using a methodology that combines wide research capabilities of of political science, psychology and sociology. The specificity of the research predefined using distant methods of data collection and processing, due to the inaccessibility of the studied personality. The biography method, content analysis and observation method were chosen as guiding. Scientific research concluded with forming a political and psychological profile of the American leader’s personality. According to the typology proposed by R. Ziller, he belongs to the category of “apolitical politician”, which indicates an overestimated self-esteem, nonconformism, and no dependence on the opinions of those around him. In addition, according to the L. Etheredge’s typology of styles of interpersonal relationships, Donald Trump is an extrovert with a high level of dominance. The political behavior of the President of the United States corresponds to the type of “agitator” in accordance with the typologies of G. Lasswell.