Abstract: 3-Mercaptopropionic acid (as stabilizer) modified CdTe quantum dots (MPA-CdTe) were synthesized. Based on the significant enhancement effect of lysozyme on the resonance Rayleigh scattering (RRS) of MPA-CdTe, a new method for the determination of lysozyme was proposed. Linear relationship between the enhanced RRS signals and the concentration of lysozyme was found in the range from 0.07 to 10.0 mg·L-1 as measured at 312 nm in a B-R buffer solution of pH 6.1, with its limit of detection (3s/k) of 0.02 mg·L-1. The proposed method was applied to the analysis of simulated sample, and values of recovery determined by standard addition method were found in the range from 93.5% to 106.0%.