In this paper, we propose a bandwidth management scheme to efficiently guarantee the QoS of various services on IMT-2000 networks. The proposed bandwidth management scheme consists of the call admission control based on the guard channel and the time slot scheduling in wireless links. For the call admission, control the preemption and deprivation method are used to overcome the problems in the previous guard channel scheme. The proposed time slot-scheduling scheme allocates time slots based on the QoS requirements of each user. The time slots are dynamically scheduled by considering the current traffic conditions with DQRUMA protocol. The simulation results show that the proposed bandwidth scheme has better performance than the previous works in terms of the handoff failure probability and the packet delay time.