Abstract: In a buffer medium of pH 5.0,a compound complex was formed between sodium hyaluornate (abbreviated as NaHA) and methyl violet,leading to a great enhancement of the intensity of resonance Rayleigh scattering (RRS) and giving a new RRS spectrum,with its maximum scattering peak at 341 nm. It was also found that the intensity of RRS was directly proportional to the concentration of NaHA in the range of 0-2.5 mg·L-1. Based on these facts,a sensitive method for the determination of NaHA was proposed. The detection limit (3σ) of this method was found to be 20.1 μg·L-1. Good selectivity of the method was shown by the results of interference test. The proposed method has been applied to the determination of NaHA in crude product of NaHA extracted from cockscomb,giving av. value of RSD′s of the results of 2.3% and av. recovery of 98.9%.