In the uncertain environment, trust and risk are both key elements for making trust-based decisions. Risk is regarded as a supplement to trust or even omitted in the most existing trust models, which will lead to one-sided or subjective decisions. To solve the issues, a risk-aware adaptive trust negotiation framework is proposed in this paper. According to the specific negotiation context, the framework analyzes the potential risks and adapts dynamic access control levels appropriately with risk management methods. The use case results indicate that this framework can identify the potential risk and adapt access control polices according to the specific entity and transaction, which avoid risks and provides more efficient trust negotiation services.