The objective of this paper is to provide an analytic framework in terms of which Japan as a model of modernization can be specified more accurately. In particular, we have tried to answer the question, 'Which aspects of Japan in which period can be a model of modernization in what sense to what types of Nations?' The following items compose the framework.. 1. Scope of relevancy (developed, developing, underdeveloped countries). 2. Period of Japan (modern, contemporary, forthcoming Japan). 3. Aspect of concern (e.g. independence, economic growth, industrialization, public administration, the military, peace, education, democracy, adoption of Western culture). 4. Aspect of application (e.g. social organization, bureaucracy, management, education, adoption of foreign techniques, entrepreneurship, nationalism) 5 . Prerequisites (e.g. natural resources, nationalities, colony, foudalism, capital formation, agriculture, industry, transport, education). 6. Function (goal, process). 7. Appraisal (positive, neutral, negative). 8. Altermative model. Arguments by Edwin O. Reischauer, Ezra F. Vogel, Yoshikazu Sakamoto and others are filtered through the framework above. Eventually three historical and three speculative models are proposed, speculative ones being the final but tentative product.