This study examines the possibility of applying radio frequency identification (RFID) technology as a method to collect quantitative data on library user behavior, and thus determine common features. An innovative method of users observation was conducted at Chiyoda Public Library in 2012. Each user was asked to carry an antenna to receive the radio waves emitted from RFID tags, and a personal digital assistant (PDA) to record the data, and went about using the library as usual. RFID tags attached to books and magazines were used to identify the locations of users. Data was obtained on the time spent in the library, travel distance, traveling path, time spent browsing in each zone and time spent browsing books by subject. It was found that the users who spent less than 30 minutes in the library made up the largest percentage of these groups, while some users spent more than 2 hours. It was also found that users tended to browse general books more than other materials.