It was the purpose of this study to investigate the effect of chitosan treatment and mordanting on the air-permeability, fastness of the dyestuff to washing, fastness of the dyestuff to light, and antimicrobial effect of cotton and nylon fabrics dyed using Rhusjara ica. In the dyeing experiment, examinations were made on the difference between the chitosan treated fabrics and chitosan untreated fabrics, and on the difference according to the type of mordanting agents and the mordanting methods. Dyeing was carried out for the chitosan treated and untreated fabrics under the conditions of non-mordanting and Al, Sn, Fe mordanting. As a result, due to the dye-uptake of the dyestuff component of the Rhusjara ica, the air-permeability values decreased considerably. And due to the action of the mordanting agents, the air-permeability decreased also. The air-permeability decreased more conspicuously in the case of the dyestuffs uptake to the chitosan components than in the case of the dyestuffs uptake to the cotton fibers or nylon fibers. Nylon dyed fabric exhibited better wash fastness than the cotton dyed fabric. As the number of washing increased, the color of the cotton fabric specimens and nylon fabric specimens, dyed using Rhusjara ica, shifted toward yellowish. The light fastness values were in the range of grade 1${~}$2, which were very inferior. The light fastness values did not improve according to the mordanting or to the chitosan treatment. In the case of chitosan untreated fabrics dyed using Rhusjara ica, the growth rate of the bacteria promoted, on the contrary, compared to that of the control white fabric.