An optical device includes a substrate, a conductive layer formed over the substrate, an insulating layer formed over the conductive layer, a first optical element disposed over the conductive layer, and a sealing resin part configured to cover the first optical element. The conductive layer includes a first conductive section, a second conductive section spaced apart from the first conductive section, and a first conductive portion extending in a first direction from the first conductive section. The first conductive portion is spaced apart from the second conductive section in a second direction intersecting with the first direction, and the insulating layer includes a first insulating part formed over the first conductive portion, and the first insulating part includes a portion overlapping with the second conductive section in the first direction.