An efficient uplink scheduling algorithm that can be used in IEEE 802.16d/e system for VoIP services is proposed to support as many voice users as possible. Our proposed algorithm requires no modification of the framework of IEEE 802.16d/e system. In this letter, we analyze the system throughput and the access delay of our proposed algorithm, and show, via OPNET simulation, that the throughput of our algorithm is superior to that of conventional algorithms in IEEE 802.16d/e system.