A light emitting device includes: a first lead including a first base portion having a constant thickness and a first small-thickness portion having a thickness smaller than that of the first base portion; a second lead including a second base portion having a constant thickness and a second small-thickness portion having a thickness smaller than that of the second base portion; wherein the first small-thickness portion and the second small-thickness portion face each other with a gap interposed therebetween; the length of the gap is 0.9 to 1.2 times the thickness of the edges of the first small-thickness portion and the second small-thickness portion; the length of the bonding wire in a plan view of the light emitting device is smaller than a value obtained by adding the thickness of the base portion, a width of a mounting-disabled area, and a width of a bonding-disabled area.