Bright organic/inorganic hybrid perovskite light-emitting diodes (PrLEDs) are realized by using CH3NH3PbBr3 as an emitting layer and self-organized buffer hole-injection layer (Buf-HIL). The PrLEDs show high luminance, current efficiency, and EQE of 417 cd m(-2), 0.577 cd A(-1), and 0.125%, respectively. Buf-HIL can facilitate hole injection into CH3NH3PbBr3 as well as block exciton quenching.