Abstract: This paper investigates the queue threshold control scheme in shared memory switches.Traditional queue control scheme employs a global threshold,which is derived from current queue length and lacks of the consideration of traffic scenarios.The presented work uses the traffic pressure as a main criterion to establish a per-queue threshold.In this sense,every output port bears the same traffic pressure.The scheme keeps the balance of the common memory in the sense of average,and relieves the demand of buffer space in times of bursty traffic.The result of simulation shows that the proposed scheme outperforms the traditional dynamic threshold in terms of efficiency.