The color difference values of dyed fabrics with colorant in Eucommiae Cortex were as follows; One hour of dyeing depending on pH at $95^{circ}C$ exhibited colors of dark brown, light brown, light beige and grey. The colors of wool, nylon and silk was darkest brown at pH 3 but light brown or yellow as pH increased. In all dyed fabrics the color was changed to darker brown as time prolonged, however; there was no further color change and value and chroma of wool declined. At pH 3, the increase in temperature turned colors of all dyed fabrics into dark brown from light yellow. As the result of repetitive dyeing, colors of all dyed fabrics gradually turned into darker brown. The methods of mordant resulted in color changes between light yellow and dark brown without various color changes.