The integration of different IP-based wireless networks, such as WiMAX and WiFi, becomes a 2-tier heterogeneous wireless networks is a more and more popular issue. In order to support multiple types of service with different QoS requirements in heterogeneous wireless networks, efficient resource management, call admission control strategies, mobility management and overflow handoff call are important issues. In this paper, we propose a resource management strategy including the call admission control, resource reservation mechanism for real-time services and Fuzzy controllers are proposed to adjusting bandwidth of real-time service with parameters dynamically. Simulation result shows that the proposed method improves the previous work (non-adaptive bandwidth borrowing reservation methods) and outperforms the traditional CAC in terms of call dropping probability and call blocking probability.