This paper investigates security control design of cyber-physical systems(CPS) under denial of service (DoS) attacks. The event-triggered predicative control(ETPC) strategy is proposed to deal with arbitrary bounded packet dropout under DoS attacks for CPS. Firstly, arbitrary bounded packet dropout in the event-triggered communication scheme is employed to describe the effect of DoS attacks by considering its energy-constraint and arbitrariness. Then, a control gain sequence derived by the latest received state is predicted to compensate the packet dropouts caused by DoS attacks at the controller side. In what follows, the security analysis and ETPC design are conducted by using Lyapunov stability theory and the switch system method. The proposed ETPC method only needs the latest received state and dose not need to satisfy with the constraint of maximum allowable packets dropouts bound in traditional stability analysis methods, which provides an effective solution for the analysis and control of CPS with large time delay. Finally the simulation results show the effectiveness of the proposed ETPC method.