Professor Toshihiko Izutsu, a Japanese Linguists, philosopher and Quranic scholar (1914-1993), in addition to his famous Japanese translation of Quran, has two main quranic books named: God and Men in Quran and Ethico-Religious concepts of Quran. In the two books basic structures of Quranic teachings have been expressed and explained. He is counted as one of followers of Ethno-linguistic school or Bon School that is one of the famous semantic schools. According to this school, each language has its own worldview. Izutsu from the school framework, studied keywords of Quran with a semantic approach, wanted to discover the meaning connections of words in a vast semantic network, in order to achieve a coherent conceptual system of Quran. He has used two semantic methods; historical and synchronic analysis. In synchronic one, he uses seven methods which have been surveyed in this article. Our main criticisms of Izutsu in this article are in these headlines: Having no attention to sentence semantic; inter-textuality; contextuality of meaning; unfamiliarity with diverse semantic schools; having no attention to the differences of opinions after descending Quran period; Having no obvious standard in to identify the axial words; and taking a mere philosophical approach to study Islamic views and neglecting rhetorical sciences.