After more than 20 years of development, semiconductor spintronics has become an important and interdisciplinary research filed of spin-based physics, materials and phenomenon. Spin light emitting diode (spin LED) is one of the fascinating topics in semiconductor spintronic, and it is also one of devices in which the radiative recombination of spin-polarized carriers results in luminescence exhibiting a net circular polarization. The research of spin LED involves the studies of materials, structures, and spin based physics in spin injector and active region. The spin injection, spin transport, and spin detection are key factors for understanding the spin based physics in spin LED. Here in this paper, we comprehensively review the current research status and the latest results. Finally, we also discuss the future research trend.