Asphalt pavement is one of the main forms of highway pavement in China. In order to make the asphalt concrete pavement function in good service state in the service life, the concept of preventive curing has been gradually developed and widely popularized. Compared with the traditional mist sealing layer technology, the sand mist sealing coat can significantly improve the skid resistance of the pavement, restore the micro cracks on the road surface, and greatly improve the driving quality of the pavement, which has become one of the effective technical measures for the preventive curing and functional recovery of highway asphalt pavement. The performances, technical characteristics, relative performance evaluation indexes and methods of sand mist sealing coat are given. The measures for ensuring the construction of sand mist sealing coat are introduced. Combined with an engineering case, the sand mist sealing coast is verified that it can effectively improve the service performance of pavement, and is a very effective preventive curing technology of asphalt pavement.