A right-angle bending waveguide includes a circular-hole-type square-lattice photonic crystal (PhC) and a single compensation scattering rod having a low refractive index. The right-angle bending waveguide is a PhC formed from first dielectric rods having a low refractive index arranged in a background dielectric having a low refractive index according to a square lattice. In the PhC, one row and one column of the first dielectric rods having a high refractive index are removed to form the right-angle bending waveguide. A second dielectric rod having a high refractive index is arranged at a corner of the right-angle bending waveguide. The second dielectric rod is the compensation scattering rod or an air hole. The first dielectric rods are circular rods having the low refractive index or air holes. The right-angle bending waveguide having the circular-hole-type square-lattice PhC and the single compensation scattering rod having the low refractive index has extremely low reflectance and a very high transmission rate, facilitates large-scale optical path integration, and provides a broader space for PhC application.