Although flash sintering (FS) is an effective method for rapidly preparing ceramics, FS of non-oxide ceramics at room temperature (RT) has not yet been achieved. In this study, we developed a feasible method for FS of SiC at room temperature (RT). A dog-bone-shape SiC sample prepared without using any sintering aid achieved a relative density of 96.5 % after sintering in a low-pressure Ar atmosphere for 60 s. Arc heating, which was constrained by the height of an alumina plate fixed above the sample, increased the conductivity of the sample, which then reached the stable stage of FS. The sintered sample exhibited a typical 6H–SiC crystal structure, which was consistent with that of the raw powder. The proposed FS method, based on constraining the arc using an alumina plate under a low-pressure inert gas atmosphere, provides a reference for developing further advanced RT FS strategies for non-oxide ceramics with low conductivities at RT.