A lamp seat includes a metal substrate having opposite first and second surfaces, first and second conductive patterns formed on the first surface, and third and fourth conductive patterns formed on the second surface and connected respectively and integrally to the first and second conductive patterns. A heat-conductive first insulating layer is disposed between the metal substrate and each of the first, second, third and fourth conductive patterns. A heat-conductive second insulating layer is formed over the first insulating layer such that corresponding parts of the first and second conductive patterns are exposed outwardly of the second insulating layer for electrical connection with positive and negative electrodes of a light emitting diode, respectively.