Based on the growth and photoluminescences experiment of Zinc Oxide (ZnO) nanorods, the structrue model of twodimensional random media, in which the location and radius of ZnO nanorods are all disordered, was constructed. Using ZnO gain model, the spectrum characteristics and spatial distribution of optical field at some resonant peak in ZnO nanorods random media were simulated numerically by means of the finite difference time domain method, and the localized mode was found. The effect of pump area on stimulated radiation of the local mode in ZnO nanorods random media was studied from four aspects: changing the pump intensity, increasing the pump size every two columns from left to right, only pumping a zone of localized mode, and increasing the excitation area (the number of the ZnO nanorods) in localized area and nonlocal area respectively when the pump intensity is fixed. The results show: there exists a critical pump power; when the pump intensity is smaller than pump intensity at the lasing threshold, no localized mode can be excited with the size of the pump area; when the pump power reaches above the critical pump power, in the case of different pump powers, localized modes can be excited with different critical pump sizes; when the power size is fixed, the relative light intensity increases with the increasing of the pump intensity and the relative light intensity increases rapidly when the pump intensity exceeds the lasing threshold.