A light emitting device is provided that can effectively dissipate heat generated by high power operation and has superior workability in mounting and less positional displacement. The light emitting device includes a planar base substrate made of a metal, a package member bonded to a main surface side of the base substrate, and an insulating member and a conductive member which are provided at least partially between the base substrate and the package member, wherein the package member has opening portions where the insulating member and the conductive member are exposed at bottom parts thereof, and the opening portions include a first opening portion in which a light emitting element is mounted and a second opening portion located separate from the first opening portion and also opening from a side surface of the package member.
