To prevent the occurrence of cracks in a secondary sealing resin by a method, wherein a photosemiconductor element is primarily sealed with a light-transmitting resin and its periphery is sealed secondarily with a non-light transmitting resin, and the light transmitting resin is formed with a thermoplastic resin.

A photosemiconductor device 20 comprises lead frames 21, 22 and photosemiconductor elements 23, 24, and the photosemiconductor elements 23, 24 are primarily sealed with a light transmitting resin 25 and further the light-transmitting resin 25 is secondarily sealed with a non-light transmitting resin 26. A main component of the light transmitting resin 25 is a transparent thermoplastic resin such as norborn are based resin, etc., and uses silica powders as an inorganic fillers. A main component of the non-light transmitting resin 26 is an opaque thermoplastic resin, and uses a glass fiber and silica powders as an inorganic fillers. By employing the transparent thermoplastic resin in the light-transmitting resin 25, occurrence of cracks is prevented and reliability is enhanced and producibility is improved.