A method and device for configuring cognitive radio system spectrum resources, relates to the field of wireless communication and solves the problem that the existing resource configuration mode influences system stability. The method includes: receiving, by a reconfiguration management node, idle spectrum resource request information transmitted by secondary user equipment, wherein the idle spectrum resource request information indicates a demand of the secondary user equipment for idle spectrum resources; and performing, by the reconfiguration management node, an idle spectrum resource configuration decision for the secondary user equipment according to current idle spectrum resource information and historical configuration information of the idle spectrum resources of the secondary user equipment. The technical solution provided by the embodiment of the present document is applicable to radio service, and realizes higher-efficiency idle spectrum resource configuration decision on the basis of historical data.