Representing political conflicts between left- and right-wing ideologies as those over economic policies is useful in evaluating the influence of politics on policies. This study considers whether such a model of endogenous policy formation is applicable to the Japanese economy. Therefore, a comparative study for Japan, Western Europe, and the United States was conducted using survey data of ideologies and preferences of economic policies. According to the results of this study, political parties in Japan have fewer differences in the preferences of economic policies than in other countries. Moreover, Japanese citizens have, to some extent, consistency between their ideologies and policy preferences.