The invention discloses a preparation method for a nano ZnO/AlN heterojunction with a high-efficient luminescence property. The preparation method comprises the following steps of 1, immersing a substrate into a mixed solution of concentrated sulfuric acid and hydrogen peroxide, performing thermal insulation at a temperature of 80-100 DEG C for 5-15min, removing oxide from the surface, then performing ultrasonic cleaning for 5-15min in acetone, deionized water and an ethanol solution separately, and immersing the processed substrate in ethanol for use; 2, preparing a zinc oxide seed layer on the substrate through a magnetron sputtering technology; 3, enabling a zinc oxide nanoarray to be grown on the substrate, which is sputtered with the zinc oxide seed layer, through a chemical solution method; and 4, sputtering an aluminium nitride thin film on the zinc oxide nanoarray through the magnetron sputtering technology to form the ZnO/AlN heterojunction. By adoption of the preparation method, the ZnO/AlN heterojunction with a low cost and the high-efficient luminescence property is obtained; the photoluminescence property of the heterojunction is quite remarkable; and therefore, effective technological support can be supplied to application of a ZnO low-dimensional structured material on the aspect of a high-quantum-efficiency photoelectric device, particularly a high-efficient blue light LED.