Abstract: The resonance light-scattering spectrum of the reaction of aminomethylsulfonic acid schiff base-phen-Ni(Ⅱ) complex and deoxyribonucleic acid has a resonance peak at 311 nm. Based on this fact,a new method for determination of deoxyribonucleic acid was proposed. The optimized conditions were as follows: ① pH of buffer solution: 7.5;② reaction temperature: 37.5 ℃;③ reaction time: 25 min;④ amount of the complex: 1.1 mL. The linear range of deoxyribonucleic acid was 0.53-7.87 mg·L-1 with detection limit of 0.16 mg·L-1. The proposed method was applied to the analysis of synthetic samples,giving values of recovery in the range of 99.7%-102% and RSD (n=9) of 1.7%.