The invention relates to a perovskite material based light-emitting diode and a preparation method therefor. The perovskite material based light-emitting diode comprises a transparent substrate layer, a transparent conductive electrode, an electron barrier layer or a hole barrier layer, a perovskite light-absorbing layer, a hole barrier layer or an electron barrier layer, and a metal conductive layer from the surface layer to the inner layer in sequence, wherein the perovskite light-absorbing layer comprises a lead halide complex; and the lead halide complex is prepared by the steps of mixing anhydrous lead halide powder with dimethyl sulfoxide solvent, or N, N-dimethylformamide solvent, or a tetrahydrofuran solution of methylamine, enabling PbX2 powder to be fully dissolved into the dimethyl sulfoxide solvent, or the N, N-dimethylformamide solvent, or the tetrahydrofuran solution of methylamine; and then adding chlorobenzene solvent, stirring, mixing, standing and filtering to obtain precipitates. According to the perovskite material based light-emitting diode and the preparation method therefor, the crystal transformation conditions of CH3NH3PbX3-nYn are lowered, the PbX2 impurity residual is reduced, the flatness of the thin film is improved, and the light-emitting efficiency of the perovskite layer thin film is improved.