A security issue in the stability analysis problem is investigated for cyber‐physical systems (CPSs) in this paper. A stability guaranteed self‐triggered scheme is proposed to actively defend the denial‐of‐service (DoS) attacks and reduce unnecessary data communications in delta domain. In the self‐triggered scheme, a predictive agent is designed, in which the stability of the CPS is considered. A transmit instant is confirmed based on the packets dropout caused by the DoS attacks and the time‐varying delays in the communication channel. Furthermore, a sufficient condition in view of linear matrix inequalities (LMIs) is derived for stability of the CPS under DoS attacks. Numerical simulations are presented to illustrate the validity of the scheme.