In this article we demonstrate the synthesis of Eu2+-doped GaN/SiO2 nanocomposites using a simple solid state reaction and their use in light-emitting devices. The nanocomposite exhibits a bright blue luminescence when excited in the UV region (quantum yield = 23 %). The origin of the blue emission is attributed to the presence of europium ions in the +2 oxidation state in the GaN/SiO2 nanocomposites. Analysis of the EPR spectrum of europium-doped GaN/SiO2 nanocomposites confirms the existence of Eu2+ in the nanocomposites. Various control experiments show that the blue emission arises from these europium ions and that the interface of GaN and silica plays a crucial role. The Eu2+-doped GaN/SiO2 nanocomposite also exhibits a bright blue electroluminescence. Furthermore, the nanocomposites can be coated with a polymer to tune their dispersibility in organic medium.