Now, the research about access control is still active. Some researchers discuss access control from new point of view. Trust has natural connection with access control. It will promote development of access control to use trust. There is a kind of access control problem we call “gambling” access control. After provider of service affords service to requestor, probability that provider gets designed results is close to probability that provider gets undersigned results. Faced to request, provider has to gamble. The traditional access control could not resolve this kind of problem. On the contrary, trust-based access control is suitable for this problem. In this paper, based on social cognitive theory, we design a trust-based access control (TBAC) with feedback. Based on provider’s goals, TBAC looks on trust to requestor as standard to whether give requestor the corresponding warranty or not. Besides, we use environment, feedback, and forecast, to realize adaptability.