Abstract: Studies the modeling, exponential stability and controller design of networked control system (NCS) with both delayed transmission time and data packet dropout occurring between sensor, controller and actuator. The NCS with time-varying delay and data packet dropout based on proportional-integral (PI) state feedback is modeled as an asynchronous dynamical system (ADS) constrained by event rates. Based on the ADS theory, principle of Lyapunov stability and method of linear matrix inequality, both the negative semi-definite matrix condition for exponential stability and the PI state feedback controller design of NCS are presented. Numerical example showed that both are feasible.