By　adding　a　dielectric　barrier,　a　hybrid　gas-solid　insulating　gap　can　be　created,　which　raises　the　withstand　voltage.　After　building　up　on　the　surface,　the　charge　will　have　an　influence　on　the　breakdown　process　and　the　distribution　of　the　electric　field.　The　saturation　state　condition　is　used　in　this　investigation　to　compute　the　surface　charge　density.　An　analysis　of　how　surface　charge　affects　the　electric　field＇s　distribution　is　done.　In　addition　to　weakening　the　electric　field　close　to　the　rod　electrode,　the　charge　also　strengthens　the　electric　field　between　the　ground　electrode　and　the　barrier.　The　surface　charge　greatly　lowers　the　electric　field　intensity　on　the　breakdown　path.　©　Published　under　licence　by　IOP　Publishing　Ltd.