As the power system gradually transform into a highly integrated cyber-physical system, The limited communication resources and DoS attacks in the network layer have challenged the stable frequency operation of power system. Therefore, this paper proposes a bidirectional adaptive event-triggered load frequency control (LFC) strategy combined with average dwell time technique. Firstly, the interconnected power system LFC system is modeled as a 0–1 switched model depending on DoS attacks. Secondly, a bidirectional adaptive event-triggered threshold update mechanism is proposed to increase the utilization of communication resources. Next, based on the average dwell time technology and Lyapunov function construction, the event-triggered parameter design and stabilization criteria are strictly derived. Finally, the proposed method are verified through the simulation of a two-area power system.