To fabricate the p-GaN/i-ZnO nanorod/n-ZnO nanorod (p-i-n) nanorod-heterosturctured light-emitting diodes (LEDs), i-ZnO and n-ZnO:In nanorod arrays were grown sequentially on a p-GaN layer. In order to passivate the non-radiatvie recombination centers at the nanorod sidewall, a thin Zn(OH)2 layer was directly grown on the ZnO nanorod using a photoelectrochemical method. Electroluminescence emission at 386 nm was observed from the resultant LEDs. Furthermore, the light output intensity of the passivated nanorod-heterosturctured LEDs was much larger than that of the unpassivated nanorod-heterosturctured LEDs. The result demonstrated that Zn(OH)2 directly grown on the ZnO nanorod sidewall could passivate the non-radiative recombination centers effectively.