The mutagenicity and desmutagenicity on enzymatic browning reaction products which obtained from prunes sazlicina (yellow) enzyme and polyphenol compounds were carried out. In the rec-assay on Bacillus subtilis strains H17 and M45, the enzymatic browning reaction products of pyrogallol, hydroxyhydroquinone, 3,4-dihydrotytoluene and catechol of 10^(-2)M did not showed mutagenicity. In the effects of various metal ions on the rec-assay, the enzymatic browning reaction products of pyrogallol showed mutagenic activity by Fe^(3+), Mn^(2+), Zn^(2+), Ni^(2+) and Al^(3+). In the enzymatic browning reaction products of hydroxyhydroquinone, Cu^(2+), Mn^(2+) and Pb^(2+) were effected in mutagenic action and the enzymatic browning reaction products of catechol was effected in mutagenic action by Mn^(2+). In the DNA-breaking action of enzymatic browning reaction products of pyrogallol, hydroxyhydroquinone, 3,4-dihyroxy-oluene and catechol did not show, DNA-breaking action. In the effects of various metal ions on the DNA-breaking action of enzymatic browning reaction products, Cu^(2+) showed DNA-breaking action. In the mutagenicity test on Sal. typhimurium strains TA98 and TA 100 with S-9 mix, 4 kinds of browned substances did sot shove muragenicity, all the browned substances showed strong desmutagenic activity in the presence of benzo (α)-pyrene with S-9 mix.