A light emitting element, in which voltages having different polarities are applied alternately in order to prevent the accumulation of electric charge in an organic compound layer of the light emitting element, and in which light is always emitted, no matter whether a positive polarity voltage or a negative polarity voltage is applied, is provided. An opposing electrode is formed between a first electrode and a second electrode, and a first light emitting element having a compound layer that contains a first organic substance between the first electrode and the opposing electrode, and a second light emitting element having a compound layer that contains a second organic substance between the opposing electrode and the second electrode, are formed in the present invention. Note that a constant voltage (reference voltage) is imparted to the opposing electrode, and that voltages having inverse polarities are applied simultaneously, and alternately for fixed periods of time, to the first electrode and the second electrode. A light emitting element that always emits light, even if the polarity of the applied voltage changes, can thus be formed.