Polymer-ceramic　dielectric　composites　have　been　of　great　interest　because　they　combine　the　processability　of　polymers　with　the　desired　dielectric　properties　of　the　ceramics.　We　fabricated　a　low　voltage-operated　flexible　organic　field-effect　transistor　(OFET)　based　on　crosslinked　poly　(4-vinyl　phenol)　(PVP)　polymer　blended　with　novel　ceramic　calcium　titanate　nanoparticles　(CaTiO3　NPs)　as　gate　dielectric.　To　reduce　interface　roughness　caused　by　nanoparticles,　it　was　further　coated　with　a　very　thin　PVP　film.　The　resulting　OFET　exhibited　much　lower　operated　voltage　(reducing　from　–10.5　V　to　–2.9　V),　a　relatively　steeper　threshold　slope　(~0.8　V/dec)　than　those　containing　a　pure　PVP　dielectric.　This　is　ascribed　to　the　high　capacitance　of　the　CaTiO3　NP-filled　PVP　insulator,　and　its　smoother　and　hydrophobic　dielectric　surface　proved　by　atomic　force　microscopy　(AFM)　and　a　water　contact　angle　test.　We　also　evaluated　the　transistor　properties　in　a　compressed　state.　The　corresponding　device　had　no　significant　degradation　in　performance　when　bending　at　various　diameters.　In　particular,　it　operated　well　continuously　for　120　hours　during　a　constant　bending　stress.　We　believe　that　this　technology　will　be　instrumental　in　the　development　of　future　flexible　and　printed　electronic　applications.　©　2020　by　the　authors.　Licensee　MDPI,　Basel,　Switzerland.