A light emitting diode is provided by the present invention which includes a pn junction-type light emitting unit having a light emitting layer (10) composed of n layers of a strained light emitting layer (12) and n−1 layers of a barrier layer (13), wherein when a barrier layer exists, the light emitting layer (10) has a structure in which one strained light emitting layer (12) and one barrier layer (13) are laminated alternately, n represents an integer of 1 to 7, and the thickness of the light emitting layer (10) is not more than 250 nm.