Spin light-emitting-diodes (spin-LEDs) composed of an epitaxial MnSb layer having in-plane magnetization and GaAs-AlGaAs double hetero-structures were prepared using a two-chamber MBE system. Electroluminescence extracted through the cleaved side walls showed elliptically polarized light emission with circular polarization of 2.1% at 30 K without an auxiliary external magnetic field. (C) 2010 Elsevier B.V. All rights reserved.