An interface for optical communication, including an input waveguide in which light input from an outside is guided, an output waveguide including a first part abutting against one end of the input waveguide and a second part connected to the first part and a substrate including a Buried oxide (BOX) layer connected to a lower side of the output waveguide, wherein the one end of the input waveguide includes a tapered structure of which a cross-sectional area is reduced by a predetermined angle.