An electroluminescent device and a method for manufacturing the same are provided to achieve a highly luminous electroluminescent device that can be used as a backlight for an LCD monitor. The electroluminescent device includes a substrate, a lower electrode layer having a surface of a plurality of convex shapes formed on the substrate, an insulating layer, a light-emitting layer, and an upper electrode layer sequentially formed on the lower electrode layer, and a passivation layer formed on the upper electrode layer. The method for manufacturing an electroluminescent device includes forming a lower electrode layer having a surface of a plurality of convex shapes on a substrate, sequentially forming an insulating layer, a light-emitting layer, and an upper electrode layer over the lower electrode layer to have substantially corresponding surface shapes as the lower electrode layer, and forming a passivation layer on the upper electrode layer.