A novel bandwidth allocation strategy and a connection admission control technique are proposed to improve the utilization of network resource and provide the network with better quality of service(QoS) guarantees in multimedia low earth orbit(LEO) satellite networks. Our connection admission control scheme,we call the probability based dynamic channel reservation strategy(PDR),dynamically reserves bandwidth for real-time services based on their handoff probability. And the reserved bandwidth for real-time handoff connection can also be used by new connections under a certain probability determined by the mobility characteristics and bandwidth usage of the system. Simulation results show that our scheme not only lowers the call dropping probability(CDP) for Class I real-time service but also maintains the call blocking probability(CBP) to certain degree. Consequently,the scheme can offer very low CDP for real-time connections while keeping resource utilization high. A novel bandwidth allocation strategy and a connection admission control technique are proposed to improve the utilization of network resource and provide the network with better quality of service (QoS) guarantees in multimedia low earth orbit (LEO) satellite networks. Our connection admission control scheme, We call the probability based dynamic channel reservation strategy (PDR), dynamic reserves bandwidth for real-time services based on their handoff probability. And the reserved bandwidth for real-time handoff connection can also be used by new connections under certain certain determined by Simulation results show that our scheme not only lowers the call dropping probability (CDP) for Class I real-time service but also maintains the call blocking probability (CBP) to certain degree. scheme can offer very low CDP for real-time connections while keeping resource utilization high.