An organic optocoupler (OOC) is fabricated with a tandem organic light-emitting diode (OLED) as the light source (input unit) and an organic photodiode (OPD) as the detector (output unit).It is found that using the tandem OLED as the input unit can significantly increase the current transfer ratio of the organic optocoupler.When the tandem OLED operates under 8 V and the OPD operates under-4 V,the current transfer ratio of the optocoupler reaches 5.4％.Simultaneously,the ION/IOFF ratio of the optocoupler reaches 105,which can be attributed to the small leakage current of the OPD,and the high efficiency of the OPD and the tandem OLED.