As a system integration framework, the role of SOA(Service Oriented Architecture) is widening and increasing day by day. The SOA framework enables software applications or computing resources to integrate flexibly and to provide more various business models. But, it is strongly required of SOA service level management for applying SOA in real business world. In this respect, we need a study on method for managing SOA system for keeping higher quality of SOA. This paper provides a new management method for SOA service level by analyzing quality factors in Web services, as SOA implementation, and negotiation/contract according to SLA methodology.