We studied the effect of carrier concentration in p‐GaN substrate on the performance of p‐GaN/n‐ZnO nanorod heterojunction LEDs. ZnO nanorods were electrodeposited on commercial p‐GaN wafers in a two electrode system from aqueous solutions of zinc nitrate and hexamethylenetetramine. The morphology and optical properties of ZnO nanorods were studied using photoluminescence and electron microscopy, and the LED device performance was studied by electroluminescence (EL) and I‐V measurements.