Poly(diallyldimethyl　ammonium　chloride)　(PDDA)　and　ferroelectric　poly(vinylidene　fluoride)　(PVDF)　composite　ultrathin　films　on　quartz　glass　prepared　by　electrostatic　layer-by-layer　self-assembly　(SA)　have　been　investigated.　Physical　measurements　of　deposited　mass　for　each　layer　were　performed　with　quartz　crystal　microbalance　(QCM),　while　the　morphology　of　ultrathin　films　was　observed　by　atomic　force　microscope　(AFM).　And　the　element　and　composite　structure　of　PDDA/PVDF　were　determined　by　X-ray　photoelectron　spectroscopy　(XPS)　and　gracing　incident　X-ray　diffraction　(XRD),　respectively.　The　surface　resistivity　and　electric　hysteresis　loop　of　ferroelectric　ultrathin　films　have　been　studied　also.　The　results　showed　that　the　thickness　of　each　layer　for　self-assembled　PVDF　ultrathin　films　on　QCM　substrate　was　about　7.5　nm,　and　the　morphology　of　composite　ultrathin　films　was　uniform.　The　binding　energy　of　F1s　in　composite　ultrathin　films　was　decreased　0.3　eV　comparing　with　the　poled　PVDF　films,　which　was　caused　by　the　distribution　of　negative　charges　as　the　re-dissolution　of　polymer.　In　addition,　the　surface　resistivity　was　improved　to　over　10(17)　Omega.　cm　for　orderly　self-assembly,　and　the　remanent　polarization　was　about　0.1　mu　C/cm(2)　for　non-ferroelectric　PVDF　in　PDDA/PVDF　ultrathin　films.