Visible light‐emitting diodes have been fabricated from Cd1−xMgxTe (x≈ 0.43). An external quantum efficiency of 2×10−4has been obtained at room temperature. Emission spectra of the diodes consist of two broad bands peaking at 640 and 700 m&mgr;, relative intensities of which depend on the concentration of Al doped as donors. The photoluminescence measurements indicate that the 640‐m&mgr; band is produced by a combination of doping P as an acceptor and heating in Cd vapor. The 700‐m&mgr; band is enhanced by Al and is attributable to lattice defects induced by Al doping.