The life-time of Sakyamuni (SM) is usually calculated backward from the date of King Asoka's coronation, which has recently been determined, as I submitted, as 268 B. C. And the period from the Nirvana (Nv. death) of SM to the Asoka's coronation is to be pursued by the traditions, which are divided into two. I. The southern tradition (the trad. of Theravada of Ceylon, or of the Pali Buddhism) says that Asoka's coronation took place 218 years after SM's Nv., and that SM's Nv. falls on the year around 480 B. C. II. The northern trad. (the trad. of the mainland of India, westnorth-India, Tibet and of China, and of the sects of Sarvastivadin, of northern Theravada and Mahasamghika, and of Mahayana) says that the reign (not the coronation) of Asoka comes between more than 100 years and not more than 200 years after SM's Nv. Accordingly, as for the year of SM's Nv., there is a difference of, roughly speaking, 100 years between the southern and the northern trads. Among those scholars who follow the northern trad., Prof. H. Ui regarded that Asoka's coronation had taken place 116 years after SM's Nv., and accordingly he concluded that SM's Nv. had occurred in 386 B. C. (he admitted that Asoka's coronation had taken place in 271 B. C.) Since then, some of the scholars of Japan followed his theory, and I also did until a few years ago. But now I have reconsidered the matter. Prof. Ui interpreted“116 years after SM's Nv.”in Chinese Shih-papu-lun and Pu-chih-i-lun, as the year of coronation of King Asoka, but this must be corrected. If one consider the meaning of the Title of those texts (Skt. Samayabhedavyuhacakra), one must interpret the sentence otherwise: i. e.“116 years after the Nv.”meant the year when the first schism of Buddhism occurred. Now, here is another problem to be considered: If the Ist schism had occurred during the reign of Asoka, the King would have spoken somewhat about the schism, an awful event to the King as well as to the Buddhism, in his many edicts, inscribed during the period from the 10th to the 27th year of his coronation. But, nothing was inscribed about the Ist schism in those edicts. Therefore, the schism must have occurred at a certain time between the 28th year (241 B. C.) and the end of his reign (232 B. C.). And, if the schism occurred 116 years after SM's Nv., the coronation of Asoka should have taken place in the year of 90 years after SM's Nv. Then it contradicts most of the traditions which tell that Asoka's reign started more than 100 years after SM's Nv. Thus, I suspect if the document itself be trustworthy.“116 years”must be the miss copy of“160 years”, judging from the records of Yuan Ed. and Ming Ed. of Pu-chih-i-lun and also of Tib. Bhavya's Ist tradition mentions“160 years”after the SM's Nv. In conclusion, I propose that SM's Nv. must be placed between 401 (241+160) and 392 (232+160) B. C., in other words, I take c. 400 B. C. as the year of SM's Nv. According to most of the traditions, SM died aged 80. My conclusion is that SM's life-time was c. 480-400 B. C., and his active life was the latter half of 5ct. B. C. This chronicle shows that SM's Nv. was about 80 years later than that of the southern trad. and about 20 years earlier than that of Prof. Ui's.