Raman D-band involves defectsin graphene,which has been a promising tool to quantify defects in graphene.Here we present thecharacteristics ofGraphene Raman D-band with differentdefect density,carrier density and excitation energy.In addition to the Raman D-band intensity increases with high defect density,wefind the Raman D-band depends on the carrier density.The Raman D-band frequency increases for hole doping and decreases for electron doping.