In this study, low-temperature cofired ceramic (LTCC) and 3D-printed ceramic interposers are designed and fabricated for a double-sided power electronic module. The interposer acts as electrical insulation between two direct-bond copper (DBC) power substrates as well as mechanical support to evenly distribute the weight of the top DBC substrate onto the entire bottom DBC substrate instead of directly onto the bare power semiconductor die. A novel LTCC fabrication process for 14 layers of green tapes with premachined recesses and holes is developed. A similar interposer is 3D printed using a ceramic resin. Finally, the fabricated LTCC and 3D-printed interposers are compared.