Since 1949 the author has received about 3500 samples sent from Universities and Laboratories in Japan. They were collected of soils of different places and of other materials (fruits, vegetables, corn, flowers, leaves, refuse, decaying matter, etc.). About 10, 000 strains were isolated from the samples, and these about 3000 strains were selected on the basis of colonial and microscopic characters. By detailed observation and continuous-monospore culture 1, 200 strains were further selected. We also examined about 150 strains of Citromyces and Penicillium, previously studied by Sakaguchi (1930) the collection of Penicillia at University of Tokyo, Penicillia sent by many investigators in Japan as unknown species, and 13 strains sent by Drs. K. B. Raper and D. I. Fennell, the University of Wisconsin, to Prof. K. Sakaguchi, the University of Tokyo, in 1952. In addition, about 600 other strains (the collection of Penicillia at Universities and Laboratories in Japan) were carefully observed by current culture. All of the 1950 strains currently described have been under observation for a period of at least three years, and some for more than five years. In this report we have described only normal strains; we did not include the yeast, sterile, and irregular types having abnormal or undeterminable penicilli and colonies, or the genera Gliocladium, Paecilomyces and Scopula-rioisis, which will be considered in other reports. All of the strains studied were assigned to species or varieties chiefly on the basis of Raper, Thom and Fennell's classification (1949), but many differences were observed from previous reports. A total 116 species and varieties were classified by morphological characters chiefly. In the previous classification mostly morphological observations are used, but in this classification the following biochemical characters were also studied and used. And, then new clssification made of (See, 33-49 page).