An optical module includes a first plate-shaped member having a light transmissive optical component which is formed by applying etching to a silicon region, and a second plate-shaped member having light reflective optical components (mirrors) for reflecting light transmitting through the light transmissive optical component. The first and second plate-shaped members are bonded to one another, and an optical path for light transmitting through the light transmissive optical component is along a component forming surface of the first plate-shaped member and a principal surface of the second plate-shaped member. Thereby, realizing an optical module in which it is possible to dispose the light reflective optical component and the light transmissive optical component close to one another, and a manufacturing method for the optical module.