This paper studies the stability analysis and state feedback controller design of continuous-time networked control systems (NCSs). A model of NCSs with multiple-packet transmission and packet dropout in both the sensor-to-controller channel and controller-to-actuator channel is given, then a stability condition for NCSs with multiple-packet transmission is presented, and a new method for controller design is also proposed by using an LMI-based method. The simulation results illustrate the effectiveness of the controller design for NCSs with multiple-packet transmission.