The lateral photovoltaic effect (LPE) is being explored as a promising method for energy harvesting and self-powered sensing. Herein we propose a free-standing SiC serpentine micro beam structure that is capable of generating a giant lateral photovoltage (LPV) of 191 mV under illumination from a 637 nm laser. We observed a photoresponse from the SiC beam even under a relatively weak illumination of 1 μW. The unique design of the free-standing SiC micro beam hinders the diffusion of photogenerated charge carriers, resulting in a high charge carrier concentration gradient, capable of generating a giant LPV. Our findings in this work demonstrate the potential for the development of miniaturized energy generators and self-powered sensors from the SiC/Si heterojunction.