An optical device (20) are formed by bonding a optical element (6) having an optical waveguide (8) with a substrate (2). On a surface of the optical element (6) facing the substrate (2) formed are the optical waveguide (8) and a thin film heater (4) that heats the optical waveguide (8). The optical element (6) and the substrate (2) are bonded through a first bonding part (12) and a second bonding part (14) made of metal material. The thin film heater (4) is electrically connected with a wire on the substrate (2) through the first bonding part (12) and the second bonding part (14). In this way, additional wires for electrical connection can be omitted, the optical element 6 can be miniaturized removing a superfluous region, and the manufacturing process can be simplified.