The paper’s analysis is aimed at the phenomenon of identity crisis in contemporary political science being revealed by the author at the different stages of historical development of American political science, in its discourse and historiography. Interpretation of the history of political science as a search for its identity suggested here makes it possible to trace historical metamorphoses of politico-scientific identity crisis through the prism of the notions of scientific soundness and political relevance of the science of politics. Incomplete or inadequate embodiment of such necessary requirements of political science repeatedly caused the identity crises of American political science in the course of its historical development. Historical analysis of ontological-epistemological, methodological and politico-institutional factors of emergence of the identity crises in American political science presented here might be significant for comprehending problems and crisis phenomena in contemporary political science as a whole.