In this paper, the performance of integrating real-time and non real-time traffic in the PCF (point coordination function) mode of IEEE 802.11 is studied, and a novel real-time traffic admission control algorithm is proposed. By changing the admission threshold dynamically according to the current load of non real-time traffic and polling the admitted real-time nodes according to their service index, the proposed algorithm can provide parameterized QoS (quality of service) for real-time traffic, while at the same time, keep the throughput of non real-time traffic at an acceptable level. The validity of the admission control algorithm is verified by simulation.