Electrochemiluminescence　assay　integrates　the　advantages　of　electrochemical　potential　controllability　and　high　sensitivity　of　luminescence　analysis.　The　electrochemiluminescence　sensor　was　fabricated　to　further　explore　the　DNA　damage.　CdS　quantum　dots　was　deposited　on　the　surface　of　glassy　carbon　electrode　in　0.　1　mol/L　CdCl2　and　0.　02　mol/L　Na2S2O3(0.　1　mol/L　HCl,　pH　2-3,　50　degrees　C)　by　cyclic　voltametry,　and　then　amino.　modified　single　strand　DNA　was　immobilized　on　CdS　modified　electrode　by　the　-CONH-　bond　using　cysteine　as　linker　agent.　The　electrochemiluminescence　was　used　to　study　the　interaction　between　perfluorooctane　sulfonates　and　DNA,　and　H2O2　was　used　as　the　common　reactant.　The　results　demonstrate　that　electrochemiluminescence　signal　value　will　be　enhanced　while　perfluorooctane　sulfonates　concentration　increases,　and　electrochemical　impedance　spectroscopy　assay　indicates　that　the　DNA　charge　transfer　attenuated　due　to　perfluorooctane　sulfonates　incubation.　These　results　reveal　perfluorooctane　sulfonates　induce　DNA　chain　distorted　and　changed.