We reported the dynamic observation about the degradation process of operating organic light emitting diodes ITO/TPD/Alq 3/Al and ITO/TPD/Alq 3:Rub/Al under ambient conditions,which is fabricated of two type staple organic materials TPD and Alq 3.OLEDs are studied via one microscopy with a CCD camera.We described the formation and growth of black spots in OLEDs,and showed that dye doped device ITO/TPD/Alq 3:Rub/Alq 3/Al is more reliable than bilayer organic device ITO/TPD/Alq 3/Al.