The adsorption behaviors of acid dye and disperse dye on silk and nylon fabrics were examined, in one bath dyeing system on silk/nylon blend fabric with disperse dyes and acid dyes. In the dyeing of nylon fabric with C. I. Disperse Red 19 (Red 19) and C. I. Disperse Red 60 (Red 60), dye uptake of Red 19 was higher than that of Red 60. When silk/nylon blend fabric was dyed with Red 19 and Red 0, the dye uptake on nylon was influenced by the ffinity of the dye to the silk fabric. In the dyeing of silk/nylon with C. I. Acid Blue 80 and C. I. Acid Yellow 121, solid shade could not be obtained with the conventional method but could be obtained with the dyeing resist agent for nylon. There was not any relationship between K/S value and Munsell value, but Munsell value tended to change with the K/S value.