This paper proposes an interactive and dynamic method—service relationship ontology-based Web service composition method (SROCM). SROCM analyzes the services relationship from three-aspects, presents a method for building the services relationship ontology (SRO). In the composition, SROCM mines the dynamic semantic of services to achieve the interests of users and gets recommend subsequence services by SRO. The semi-automatically method can get an optimized service matchmaking result, adapt for variety of requirements of both customers and service providers flexibly, and ensure efficiency while composing service. The preliminary experiments show that this method can provide excellent subsequent service according to user's interests, and it is feasible and effective in dynamic service composition.