The　traditional　harmonic　responsibility　division　method　is　difficult　to　be　fully　immune　to　the　variation　of　background　harmonics　and　harmonic　impedance　of　power　system,　and　lacks　the　overall　consideration　of　harmonics　at　different　orders.　To　solve　the　above　problems,　according　to　the　mechanism　of　harmonic　generation,　a　harmonic　responsibility　division　index　based　on　load　equivalent　impedance　parameters　is　proposed.　The　index　can　quantify　the　harmonic　responsibility　of　each　feeder　under　a　single　bus.　Furthermore,　a　two-point　load　impedance　parameters　estimation　method　is　proposed　for　three-phase　symmetrical　load　that　avoids　the　problem　of　abnormal　value　caused　by　zero　crossing　of　denominator,　which　lays　an　application　foundation　for　harmonic　responsibility　division.　The　feasibility　and　effectiveness　of　the　proposed　index　and　method　are　verified　by　example　calculations.　©　2023　Science　Press.　All　rights　reserved.