To predict new materials with special electronic and optical properties can be considered as an effective procedure to design new potential applications. In this article by using density functional theory (DFT), a new two-dimensional structure of antimony carbide is theoretically predicted. Our DFT based simulations show that the proposed monolayer is energetically, kinetically, and thermally stable. By more investigation on its physical properties it is found that the Sb2C monolayer is an indirect semiconductor with interesting electronic and optical properties can be effectively modulated by biaxial external strains and has potential applications in new electronics technology.