Abstract: In an acetate buffer medium of pH 3.80 and in the presence of CTMAB,a stable red ternary complex was formed among Au(Ⅲ),chlorophenolazo rhodanine and CTMAB in the mole ratio of 1 to 3 to 1 respectively.Absorption maximum was found at the wavelength of 490 nm,where the apperent molar absorptivity was found to be 3.2×105L·mol-1·cm-1.Linear relationship between values of absorbance and concentration of Au(Ⅲ) was obtained in the range within 700 μg·L-1,in accordance to the linear regression equation of A=0.162 4 C+ 0.029 21 (r=0.999 8).The proposed method was used to determine microamounts of Au(Ⅲ) in 2 samples of gold ore,giving average values of recovery 98.0%.