Disclosed is a light emitting device (1) comprising a rectangular element (10) mounted upon a mounting substrate (20) via a heat-melted connecting material, wherein second substrate electrodes (3) are formed conforming to the recesses (2c) of a first substrate electrode (2) and a portion of the outer periphery of the first and second substrate electrodes (2,3) is provided with first extended sections (2b) that extend farther outward than the outer periphery (gs) of the aforementioned element (10). The aforementioned first extended sections (2b) are formed in at least one or more locations per one side of the outer periphery (gs) of the aforementioned rectangular element (10); the aforementioned first substrate electrode (2) is provided with second extended sections (2d) that are formed on at least one of both ends of the aforementioned recesses (2c) flanking the first extended sections (2b) of the aforementioned second substrate electrodes; and the aforementioned second extended sections (2b) extend farther outward than the outer periphery of the aforementioned element (gs).