The invention relates to an alkali halide-doped perovskite light-emitting diode. The alkali halide-doped perovskite light-emitting diode comprises a substrate, a hole transmission layer, an active light-emitting layer, an electron transmission layer, an electrode modification layer and an electrode, wherein the thickness of the active light-emitting layer is 5-100 nanometers, the active light-emitting layer comprises perovskite and an alkali halide doped in the perovskite, the molecular formula of the perovskite is one or more of CsPbCl<x>Br<3-x>, CsPbBr<x>I<3-x>, MAPbCl<x>Br<3-x>, MAPbBr<x<I<3-x>, FAPbCl<x>Br<3-x> and FAPbBr<x>I<3-x>, x is equal to 0, 1, 2 or 3, and the alkali halide is one or more of LiCl, NaCl, KCl, RbCl, LiBr, NaBr, KBr, RbBr, LiI, NaI, KI and RbI. The invention also provides a fabrication method of the alkali halide-doped perovskite light-emitting diode. The fabrication method comprises the steps of forming the hole transmission layer or the electron transmissionlayer o the substrate; modifying an alkali halide-containing perovskite precursor solution used as the active light-emitting layer on the hole transmission layer of the electron transmission layer; sequentially forming the electron transmission layer, a negative electrode modification layer and a negative electrode on the active light-emitting layer or sequentially forming the hole transmission layer, a positive electrode modification layer and a positive electrode on the active light-emitting layer; and performing package.