Supervision on the construction and hazard control of small and medium-sized water works is a highly intelligent technical service. To supervise under the terms of the contract and business regulations, and to send chief supervision engineers for site tracking, inspection and  site supervision can guarantee the construction quality, investment and construction period. Main research achievements in aspect of supervision on small and medium-sized water works are presented as follows: the definition and classifications of small and medium-sized water works, principles of supervision, control before, during, and after the construction, contract management and information management, organization coordination, and environmental protection and eco-balance, as well as the system of supervision evaluation. Application examples are also given.