The purpose of this study is to investigate dyeing properties of wool fabric with walnut colorants. Walnut colorants were extracted with water from walnut hull and characterized by FT-IR analysis. Effects of dyeing conditions and mordanting on dyeing properties and colorfastness were studied.Results obtained were as follows；1. Higher K/S value was obtained at higher temperature and longer dyeing time, the highest K/S value was shown at 100℃, 60min.2. Dye uptake was increased with the increase in colorants concentration up to 2%. Higher K/S value was obtained at acidic condition. 3. Mordanting was not effective for improving dye uptake and colorfastness and for changing color of the dyed fabric.