The steel bar connection technology is one of the key construction technologies in the prefabricated concrete structure, and the steel bar connection is generally carried out by grouting sleeve. In recent years, grouting sleeves have been used more and more in prefabricated building components in China, but the time of application in bridge is relatively short. This paper introduces the test and research of grouting sleeve bar connection technology in precast pier, mainly from the research background, connection structure and material properties, bond stress study, type test, seismic test of precast assembled column, etc.