An optical module includes a substrate and terminals. The substrate has: a first planar part having first through holes into which the terminals are inserted respectively; a second planar part that opposes the first planar part as a result of the substrate being folded and has second through holes into which the terminals are inserted respectively; at least one first land part that is formed on the first planar part around at least one of the first through holes and that is connected to at least one of the terminals inserted through the first through hole; and at least one second land part that is formed on the second planar part around at least one of the second through holes into which another one of the terminals not being connected to the first land part is inserted and that is connected to the terminal inserted through the second through hole.