The ability to create nanoengineered silicon carbide (SiC) architectures is important for the diversity of optical, electronic, and mechanical applications. Here, we report a fabrication of periodic three-dimensional (3D) SiC nanoscale architectures using a self-assembled and designed 3D DNA-based framework. The assembly is followed by the templating into silica and subsequent conversion into SiC using a lower temperature pathway (<700 °C) via magnesium reduction. The formed SiC framework lattice has a unit size of about 50 nm and domains over 5 μm, and it preserves the integrity of the original 3D DNA lattice. The spectroscopic and electron microscopy characterizations reveal SiC crystalline morphology of 3D nanoarchitectured lattices, whereas electrical probing shows 2 orders of magnitude enhancements of electrical conductivity over the precursor silica framework. The reported approach offers a versatile methodology toward creating highly structured and spatially prescribed SiC nanoarchitectures through the DNA-programmable assembly and the combination of templating processes.