An omnidirectional semiconductor light emitting device lamp has a light distribution characteristic having a large range similar to that of a general incandescent lamp. The semiconductor light emitting device lamp includes a light emitting device for emitting light in all directions and reflection plates arranged at a front surface and a lateral surface of the light emitting device. The light emitted from the light emitting device is reflected from the reflection plate located at the front side and the reflection plate located at the lateral side and emitted to a rear side of the light emitting device. A reflection film is formed on all exposed portions of a surface of the substrate on which the light emitting device is mounted.