At the present stage, automated service negotiation faces a dilemma. On the one hand, it's autonomous such that agents are capable of making decisions about what actions to take without constantly referring back to its user [7]. On the other hand, the system is trustworthy in the sense that the agents should make their users believe that it will act to achieve their business goals (i.e. the users are able to guide and control the behalf of agent). To deal with conflicts between "autonomous" and "trustworthy", this paper represents a policy-based framework which composes of information and policy part. Information part provides knowledge and policy part control agent negotiation strategy. Under this framework, users define their business goals in abstract policy. Then, the abstract policy is refined to concrete policies whose strategy can be implemented by different heuristic methods. Thus, the framework helps to eliminate the conflict between 'autonomous" and "trustworthy". After describing the framework, we then went on illustrating its use in our prototype system.