To provide a lead frame which requires less component count and assures easy manufacturing, and to provide an optical coupler device using such a lead frame.

The optical coupler device using the lead frame comprises a light-emitting element, a photodetector arranged in opposition to the light-emitting element at given intervals, a first electrode lead section 12 with the light-emitting element positioned at one side and with a remaining lead section folded back like an L shape on the opposite side of the photodetector on the way and extended to the outer side of the light-emitting element at the other side, and a second electrode lead section 14 with the photodetector positioned at one side and with a remaining lead section folded back like an L shape to the light-emitting element side on the way and extended to the outer side of the light-emitting element at the other side. A concave portion 31 is formed in a region where a light-emitting section 21 and a photodetector section 22 each of which molds the light-emitting element and the photodetector respectively with a transparent resin against the light-emitting wavelength are placed in opposite to each other, and windows 32 and 33 are formed to pass the received/emitted light to the opposing sidewalls, then the whole area is molded with an opaque resin 34.