With the continuous appearance of WLAN technology standards and relevant products based on these  standards,the application and extension of WLAN have reached a new stage. What influences on WLAN technology of library network and how to apply WLAN technology into the construction of library network have been the focus to which people pay attention increasingly.This article introduces some conceptions and technology of WLAN,puts forward some construction modes of WLAN in library,and based on personal practice, the paper analyzes the realization of wireness electronic reading room in library.