Light emitting element mounting base member, and light emitting device using the light emitting element mounting base member

A light emitting element mounting base member for mounting a light emitting element having an n-side electrode and a p-side electrode on a same side of the light emitting element, the light emitting element mounting base member comprising:

• a plurality of electrical conductor cores;
• a plurality of light-reflecting insulating members, each of which covers a lateral surface of each of the plurality of electrical conductor cores, the plurality of light-reflecting insulating members having a reflectivity of 70% or more to light emission wavelength of the light emitting element in a range of 440 nm to 630 nm;
• and
• a light blocking resin that joins at least two insulating members of the plurality of light-reflecting insulating members, the light blocking resin which is capable of blocking light from the light emitting element by reflecting or absorbing the light,
• wherein at least one upper surface of the plurality of electrical conductor cores, at least one lower surface of the plurality of electrical conductor cores are exposed from the plurality of light-reflecting insulating members and the light blocking resin respectively.