Radio spectrum is the basic and essential resource in broadband wireless networks, however it is quite scarce. With the growing scale of wireless network, the limited spectrum resource cannot meet the demand of exploding mobile traffic. To alleviate burden of networks and improve resource utilization, much efforts have been devoted to efficient mechanisms of spectrum management. This paper first summarizes the fundamental knowledge of spectrum in wireless communications and the challenges faced by spectrum utilization. It then categorizes and evaluates the existing spectrum resource management methods in broadband wireless networks from the aspects of traditional static management and prevalent dynamic management. Finally, it offers a prospect of future research development concerning frameworks and key issues towards dynamic spectrum management.