The new technology, RSS(Really Simple Syndication), allows people to send and receive a lot of up-to-date information by constant monitoring websites and databases for new information, without having to visit the site or database. The "gatekeeping" task for capturing and delivering various information influx via new digital channels as speedy as possible, is being discussed as a new form of service in the field of information service system nowadays. Given this situation, the RSS tool can be greatly useful in the gatekeeping task. This paper, by analyzing concrete cases in which RSS is actually employed in libraries and also newly applied to other diverse information services in France, expects to provide insightful ideas for developing innovative information services in other countries.