The purse of this study was to invesigate the dyeing fastness on extract of bufferbur leaf princeps. The experimental items were divided into the mordant treatment, component of fabric and kind of mordants. The experimental study was done by laundering, abrasion (dry/wet), perspiration (acid/alkali), light, iron fastness test and color difference by C.C.M system. The summerized finding resulted from experiments and investigation are suggested as follows : In the C.C.M test on mordanting method and kind of fabric, color difference of silk was three times higher than cotton. The silk fabric was the highest in simultaneous mordant treatment but cotton fabric was the highest in none mordant. In color difference analysis on 6 mordants, that of silk and cotton was significantly improved when mordants was treatmented. Especially color difference of Fe and Cu mordanting treatment was higher than Cr, Sn, Al and none. In dyeing fastness on mordants laundering, perspiration, abrasion and iron fastness showed 4-5 grade but light-fastness showed 1-3 grade.