The number of network services and traffic is increasing, the number of Service Function Chains (SFC) that cannot meet the latency requirements gradually increases, reducing the SFC service quality. To address this issue, this article constructs a network resource model, analyzes the physical network features and the SFC features, and proposes a network resource scheduling mechanism with controllable delay in the SFC. The main steps of this mechanism include setting the threshold level of physical network resource usage, setting the types of available resources in the SFC, and migrating the SFC. Comparing this mechanism with existing mechanisms, it was verified that using this resource scheduling mechanism to schedule resources for the SFCs can meet more latency requirements of the SFCs and improve the network resources utilization.