In recently years, broadband wireless access, an attractive technology to support various applications in our daily life, has been developed rapidly. Those applications usually have QoS requirements, such that packet loss ratio and delay bound. Therefore, it is important to design a scheduling scheme that provides QoS and uses spectrum efficiently. In this thesis, we propose a two-stage scheduling scheme in OFDMA-based wireless system. Flows are divided into two sets and served with two resource allocation algorithm in two stages. The simulation results show that our proposed scheme can serve more flows than previous work, under the same QoS requirements.