The experiment was tested with fruit of 5 astringent cultivars (Chungdo-Bansi, Sagoksi, Enisung-Bolbansi and Gyungsan-bansi) and was carried out to investigate effects of harvest time of fruit and fruit sizes on the removal of astringency and the practical utilization with Chungdo-Bansi was conducted. 1. Soluble tannin content was decreased in all cultivars as fruit was ripening and soluble tannin content at last harvest time was reduced about one half, as contrasted it`s content at first harvest time and it showed that the times reqired of the removal of astringency was gradually shortened. 2. In soluble tannin contents was small fruit size was significantly higher than that of large fruit size. The times for the removal of astringency was required longer small fruit size than large fruit size. 3. In the changes of hardness according to fruit sizes, hardness of large fruit size was decreased rapider than that of small fruit size. This tendency became similar during and after the removal of astringency. 4. According to fruit sizes, sugar content of large fruit size was more amount than that of small fruit size During and after the removal of astringency, reduction of sugar content showed more rapidly large fruit size than small fruit size. 5. Results of the practical utilization in Chungdo-Bansi showed the promising market ability and persimmons treated by carton dioxide was increased more income than that treated by CaC₂.