A drop in the luminous efficiency of a light-emitting element and the occurrence of mounting problems for the light-emitting element can be prevented even in a configuration in which an ESD protection element is provided within a mounting substrate. A light-emitting device (10) includes a light-emitting element (2) and a mounting substrate (11), having a first surface (11A) on which the light-emitting element (2) is mounted and a second surface (11B) that is opposite from the first surface (11A), that includes a semiconductor-based electrostatic discharge protection element portion (15) that is provided on the second surface (11B) side and is connected to the light-emitting element (2)
