The characteristics of resonance light scattering (RLS), UV-visible absorption spectra and fluorescence spectra of ［Cu(DPPZ)(L-Ser)］+ with DNA were studied and a RLS method for the determination of DNA was established.［Cu(DPPZ)(L-Ser)］+ could assemble on the surface of DNA through intercalation, and enhanced the RLS of DNA in the tris buffer of pH 7.2.The maximum resonance light scattering peak appeared at 400 nm.Under the optimum conditions, the enhanced intensity of RLS was proportional to the concentration of DNA over the range of 0.42～4.2 ng·mL-1, with a detection limit (3σ/k) of 0.29 ng·mL-1.The method was used for the determination of DNA samples with the recoveries between 97.8% and 106%.