This paper explores the result of a questionnaire survey on the location decision of new manufacturing plants from 1997 to 2004 and discovers an industrial cluster in Japan. More specifically, performing an exploratory factor analysis across 22 manufacturing industries, this study firstly summarizes agglomeration advantages as a latent location factor, secondly specifies the regional share of industries that emphasize the agglomeration factor, and thirdly identifies the location of industrial cluster based on the regional share. The major finding is that there exists such agglomeration factor, by which most Marshallian location advantages are represented, and the main industrial cluster consists of high-tech industries and spread over the suburb area between Tokyo and Aichi prefectures, where are most manufacturing capacity is concentrated.