Delay guarantees are critical for the fast-growing network services that require low delay. Selecting the appropriate routing path for services with delay requirements is an important aspect of ensuring low delay. However, traditional routing mechanisms may have a negative impact on the delay of existing network services, as they primarily focus on satisfying the delay requirements of new services. In this paper, we present a delay guaranteed routing mechanism for software-defined network (SDN). Our mechanism employs a combination of active and passive delay measurements to determine the delays of multiple paths between the source and destination switches, and then chooses paths for services based on the load of the links on these paths and the delay requirements of the services. We also propose a rerouting mechanism in case the service delay cannot be fulfilled. The simulation results show that our proposed method provides better delay guarantees for network services.