The packaging of micro electro mechanical systems (MEMS) is referred to first-level packaging and limited generally to the preservation of wafer in this paper. It is based on bulk silicon bonding technology and film sealed technology. The bulk silicon bonding technology includes electrostatic bonding, silicon direct bonding and interfacial layer assisted bonding. It is used for making material acting as substrate or cover of the chip. The film sealed technology includes whole-wafer operation, local-wafer operation and selective preservation. It is used to seal micro channel or micro hole to form a vacuum or low-pressure cavity or protect from atmosphere influence. The very high importance not to forget packaging at the beginning of a project, when hoping to industrialize MEMS is discussed. In order to obtain high performance-price ratio,it is necessary to weigh the device performance against the chip complexity. The commercialized pressure sensors, accelerometers, digital micro mirror devices, etc., collected from literatures are used as examples.