A　polymer　barrier　inserted　in　the　interelectrode　gap　can　significantly　improve　the　insu-lation　performance　of　air-insulated　high-voltage　electrical　equipment.With　the　devel-opment　of　power　equipment　towards　integration　and　miniaturisation,multiple　barriers　can　be　used　to　further　increase　the　insulation　level.This　paper　investigated　the　withstand　characteristics　of　the　air-insulated　rod-rod　gap　with　multiple　barriers　by　changing　the　barrier　numbers,the　barrier　position　and　the　barrier　insertion　direction.Four　control　modes　were　set　up　based　on　the　assumed　breakdown　paths　under　alternating　voltages.It　was　found　that　the　control　modes　with　barriers　inserted　from　the　opposite　direction　had　a　more　significant　improvement　effect　than　that　from　the　same　direction.When　the　hor-izontal　barrier　position　was　closer　to　the　electrode　and　the　vertical　barrier　position　was　farther　to　the　electrode　axis,the　breakdown　voltage　was　higher.The　vertical　barrier　position　was　a　key　factor　affecting　the　probability　of　breakdown　path　type,and　the　breakdown　voltages　along　different　types　of　breakdown　paths　were　almost　the　same　when　the　barriers　were　at　the　same　position.The　increase　of　the　breakdown　voltage　was　mainly　resulted　from　the　change　of　electric　field　distribution　in　the　insulated　gap　and　the　extension　of　the　breakdown　path　length.