Communication: Three-dimensional hyperbranched polymers are shown to be new candidates for emitting materials in light-emitting devices (LEDs). Owing to the properties of hyperbranched polymers, devices incorporating them are expected to have improved stability and efficiency compared to LEDs made from linear polymers. The performance of a bilayer electroluminescence device is reported in which the electron-transport layer is made of a hyperbranched polycarbazole and a newly synthesized linear polymer constitutes the hole-transport layer.