The sealing technology for confined-artesian monitoring wells is developed for urgent problems in drilling of groundwater monitoring wells， such as sealing， monitoring， sampling and well development. With the technology， a stainless steel sealing cover plate with multiple functional components is installed at the wellhead of the monitoring well to meet the requirements of the artesian monitoring well. This paper introduces the sealing technology principle， system composition， installation process and sealing method for the confined-artesian monitoring well. The field demonstration shows that the technology can effectively solve a series of problems， such as wellhead sealing， water sampling， well development， maintenance of probes； provide the advantages of good sealing effect， zero water pollution， convenient operation and low cost， and realize long-term automatic collection and transmission of groundwater data from artesian monitoring wells with different characteristics. It can provide a approach for the sealing work of similar wells.