A resonance light scattering (RLS) spectrometry for determining DNA based on localized surface plasmon resonance (LSPR) of gold nanorods was developed. The fabrication and characterization of the biosensor utilized gold nanorods as the optical transducer was described. The DNA was determined based on the binding of DNA to gold nanorods by electrostatic adsorption. The RLS intensity of the gold nanorods was enhanced in the presence of DNA. The peaks of the enhanced RLS spectrum were at the wavelength 311 and 581 nm. The binding of DNA to the gold nanorods causes an increase of the RLS intensity that is responsive to the concentration of DNA. Under the optimal conditions, the enhanced RLS intensities are directly proportional to the DNA concentrations in the range of 0.05-0.5 microg/mL. The proposed method was successfully applied to the determination of DNA in the samples and the results were satisfactory.