We investigated the contents of ascorbic acid, astragalin and polyphenols, and the 1，1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of 22 commercial persimmon leaf tea products. There were marked differences in the ascorbic acid content among the products (0-1,300 mg/100 g dry weight (DW)).The astragalin content of the products ranged from 0 to 219 mg/100 g DW, the polyphenol content ranged from 900 to 6,070 mg of catechin eq．/100 g DW, and the radical scavenging activity ranged from 12 to 41mmol Trolox eq．/100g DW. We determined the effects of water content, roasting temperature, and roasting time on the ascorbic acid content, polyphenol content, and DPPH radical scavenging activity to clarify the reasons for the differences among these persimmon leaf tea products. The results suggest that the optimum conditions for retaining the ascorbic acid content, polyphenol content, and DPPH radical scavenging activity were a water content of 5% or less and non-roasting. A low temperature of approximately 150°C was the most suitable for a roasting treatment．
