Biphenyltetracarboxylic　dianhydride　(BPDA)　and　4,　4＇-diaminodiphenyl　ether　(ODA)　used　as　monomer　reaction　products　and　the　polyimide　(PI)　dielectric　films　have　been　successfully　fabricated　via　solution　polycondensation.　The　structure　and　surface　morphology　of　PI　dielectric　films　prepared　in　different　imidization　temperature　were　characterized　by　XRD,　SEM　and　FT-IR.　The　influence　that　the　imidization　temperature　and　powder　content　(BPDA　and　ODA)　affected　on　the　breakdown　field　was　measured　by　current　testing　instrument　with　high　resistance　techniques.　The　experimental　results　show　that　polyimide　acids　(PAA)　were　completely　aminated　and　become　PI　dielectric　films　with　compact　internal　structure　after　imidization　temperature　of　300°C　for　1h　under　vacuum　environment　of　1.0×10-2Pa.　The　breakdown　field　can　reach　up　to　2.15MV/cm　when　powder　content　of　BPDA　and　ODA　was　fixed　to　5%,　which　indicates　that　PI　dielectric　films　have　good　electrical　properties.