The use of hybrid organic-inorganic perovskites in optoelectronic applications are attracting an interest because of their outstanding characteristics, which enable a remarkable enhancement of device efficiency. Here, we demonstrate highly efficient perovskite lgiht-emitting diodes by surface treatment to passivate the defect sites of methyl ammonium lead tribromide (MAPbBr3) with uniform morphology. This treatment greatly enhanced PeLEDs efficiency, with an improved external quantum efficiency (EQE), enhanced photoluminescence (PL), a lower threshold for amplified spontaneous emission (ASE), a longer PL lifetime and enhanced device stability.