The problem of modeling and stabilization of a wireless networked control system(NCS) with both packet dropout and time-varying delay is investigated in this pa-per, and the time-varying delay is more or less than one sampling period. The closed-loop wireless NCS is modeled as an asynchronous dynamic system(ADS) with three subsystems. By using the ADS approach, a sufficient condition for the closed-loop wireless NCS to be stable is presented. An illustrative example is provided to demonstrate the effectiveness of the proposed result.