The article deals with the methodological problems of transformation processes in political science in the late XIX-th-early XX centuries and in the period between the two world wars. The author reveals the causes and origins of the crisis phenomena in political science due to the new political realities in the world and new trends in the political science development. The process of modern political science formation is analyzed in its gradual development (formal-legal, traditional, behavioral and post-behavioral). The special role of the Chicago revolution in political science, which created the environment and the ground for the emergence of the “behavioral” revolution, is revealed. The main program provisions of the “behavioral” revolut...