The WiMAX features longer transmission distance and more accomplished support of QoS than other wireless access technologies such as 802.11. Since the standard did not specify the QoS based packet-scheduling algorithms which run on the base stations, those algorithms are open for alternative implementations. In this paper, we propose a scheduling algorithm for burst traffic in the WiMAX base station with reference scenario being a typical PMP deployment. Since most existing studies use strict Priority Queue (PQ) for different classes of services, it leads to starvation of lower priority services when the higher priority traffic is heavy. Our proposed algorithm aims to achieve better fairness than the previous approach and improve the throughput of burst data, yet still meets the QoS demands including delay constraint and minimum bandwidth requirement.