Abstract: The title constants were determined by reverse-phase HPLC on an ODS column with methanol as mobile phase. The samples were treated with light and measured without interference. The physical and chemical quenching rate constants of 5 different kinds of quenching agents and singlet oxygen were determined. The results show that during the quenching process of singlet oxygen physical quenching is the main factor. To certain degree, the larger the physical and total quenching rate constants, the better the anti-fading effect of magenta azomethine dye.