Abstract: 3.00 mL of Britton-Robinson buffer solution (pH 3.29), certern volume of 8.8×10^-6mol·L^-1 bovine serum albumin solution, and 0.40 mL of 1.00×10^-3mol·L^-1 2-2-(5,6-dichlorobenzothiazolyl)azo-5-dimethylaminobenzoic acid solution, were added into a 10 mL colorimetric tube successively. After 35 g of NaCl was added, the mixture was made up to 10 mL with water, shaked well, and reacted at 35℃ for 3 h. Then the resonance light scattering intensity of the system was mesured at the excitation wavelength and the emission wavelength of 524 nm. Linear relationship was found between the resonance light scattering intensity of the system with the concentration of bovine serum albumin in the range of 1.00-25.00 μmol·L^-1, and the detection limit (3S/N) was 0.33 μmol·L^-1. The method was applied to determination of the content of bovine serum albumin in bovine urine, gving values of recovery between 99.6% and 102%, and RSDs (n=6) between 1.8%-5.8%.