In　this　paper,　a　3D　printed　flexible　force　sensor　is　proposed.　The　force　sensor　consists　of　the　top　and　bottom　layers　fabricated　by　a　digital　light　processing　(DLP)　based　3D　printer　with　polyurethane　acrylate　(PUA).　Micro-pyramid　arrays　are　designed　on　the　surface　of　the　bottom　layer.　The　surfaces　of　both　top　and　bottom　layers　are　then　coated　with　poly　(3,　4-ethylenedioxythiophene)　polystyrene　sulfonate　(PEDOT:　PSS)　film　as　the　stretchable　electrode.　The　sensing　principle　bases　on　the　changes　in　resistance　between　the　top　and　bottom　layers　since　the　contact　area　increase　due　to　the　deformation　of　the　Micro-pyramid　arrays　with　applied　force.　Finally　the　force　sensor　is　characterized　within　the　force　range　from　0　to　392mN.　This　work　demonstrates　that　3D　printing　technology　has　a　good　application　prospect　in　sensor　manufacturing.