Disclosed herein is an AC light emitting diode. The light emitting diode comprises a plurality of light emitting cells two-dimensionally arranged on a single substrate. Wires electrically connect the light emitting cells to one another to thereby form a serial array of the light emitting cells. Further, the light emitting cells are spaced apart from one another by distances within a range of 10 to 30 D, and the serial array is operated while connected to an AC power source. Accordingly, the excellent operating characteristics and light output power can be secured in an AC light emitting diode with a limited size.