Substrates　used　in　flexible　electronics,　electronic　clothing,　wearable　devices,　soft　robotics,　etc.,　need　to　have　the　properties　that　include　functionally　gradient　variable　rigidity,　excellent　heat　dissipation,　and　biocompatibility.　Nevertheless,　these　criteria　cannot　be　met　well　by　the　current　substrates.　A　functionally　gradient　substrate　PDMS/SiC　is　proposed　using　the　PDMS　as　a　matrix　material　and　the　SiC　as　a　reinforcing　step　(filler)　and　the　SiC　content　gradient　distribution.　To　address　the　challenging　issue　of　manufacturing　PDMS/SiC　functionally　gradient　substrate,　a　novel　method　of　manufacturing　using　a　multi-material　3D　printing　process　with　active　mixing　nozzle　is　proposed　to　create　the　functionally　gradient　substrate　at　low　cost　and　high　throughput.　The　PDMS/SiC　functionally　gradient　substrate　is　obtained　by　combining　the　proposed　approach　with　optimized　parameters.　Compared　to　traditional　PDMS　substrates,　the　latest　substrate＇s　thermal　conductivity　is　increased　by　2.5　times,　and　50%　side　Young＇s　module　of　SiC　material　is　increased　by　2.9　times.　Besides,　the　substrate＇s　rigidity　varies　gradually.　The　experimental　findings　show　that　the　functionally　gradient　substrate　PDMS/SiC　provides　a　new　high-performance　substratum　for　flexible　electronics,　electronic　skin,　wearable　electronics,　soft　robot,　etc.　©　2020,　Science　Press.　All　right　reserved.