For the purpose of standardization and practicability of nautral dyeing, the mordanting and dyeing properties of Rhusjara ica was studied. Appropriate extraction, dyeing and mordanting condition of Rhusjara ica were determined, and the effect of mordanting method on dye uptake and color fastness of dyed fabric was investigated. The most absorbance of Rhusjara ica solution was 299 nm. The color of Rhusjara ica solution was affected by pH 8~9. The optimum temperature to extract Rhusjara ica was 6$0^{circ}C$ and dyeing solution for 1 hour. Effective dyeing time to silk was 60min. Effective mordanting temperature was 80~10$0^{circ}C$, and its time was 30 min. K/S value of dyeing fabrics was recoginazed by mordanting treatment, specially Fe, Al, Cu. K/S value of pre-mordanting was higher than post-mordanting. In the case of Rhusjara ica fastness was increased by mordanting treatment.