A biological information detector has a light-emitting part including an LED, a first connecting pad, a first bonding wire, and a light transmission part. The first bonding wire electrically connects the light-emitting part and the first connecting pad. The light transmission part transmits light emitted by the light-emitting part. The light transmission part covers the light-emitting part and the first bonding wire. A thickness of the light transmission part is from 1 μm to 1000 μm.