Abstract: Ion mobility spectrometry (IMS) is a trace gas detection technology developed from the seventies of last century. There are lots of advantage for IMS, such as simple structure, fast detection speed, atmospheric pressure working environment. It has a great potential for development of in the miniature and portable application. This paper introduced the basic principle of ion mobility spectrometry. We put emphasis on the research of ionization technique basic on IMS, and include outlooks on its future development.