UV random lasing in p-i-n ZnO-based heterojunction diodes is achieved. The UV emission originates from the use of an intrinsic ZnO-SiO2 nanocomposite layer; the use of ZnO powders can improve the electrical-to-optical conversion efficiency of the heterojunction. The patterned ZnO clusters in the SiO2 matrix enhance the quality of the random media (see figure) thus sustaining the random lasing action. If low-index, p-doped, wide-bandgap materials are used as the hole-injection layer, strong coherent random lasing could be achieved.