Based on the service plane (SP) of Adaptive Multi-Service Optical Network (AMSON), this article designs and implements optical service level agreement (O-SLA),which meets the clients' requirements and improves the performance of the optical network. Our Adaptive Multi-Service Optical Network (AMSON) testbed is based on the framework of Automatic Switched Optical Network (ASON), and introduces a service plane (SP) into it as an independent functional plane. SP receives and processes the service requests submitted by the clients. An O-SLA is a formal contract between an optical network service provider and a service subscriber that contains various service levels and diverse clients' requirements. We focuses on designing and implementing O-SLA on SP of AMSON by introducing O-SLA to Bandwidth on demand (BoD). BoD is a kind of service initialized by clients in SP and can be adjusted dynamically. We classify three levels for the contents of O-SLA that enable the clients to get three kinds of authorization. To conduct this O-SLA, the network operators should publish relevant information to SP. According to this information and O-SLA, the related modules of SP can lay out proper instructions to CP. Then appropriate operation will be done by CP and the results of it will be returned to SP. Some simulations have been done and results are given, which illustrate that the implementation of O-SLA combined with BoD on SP of AMSON induces the blocking rate and improves the utilization of the network resource.