In this paper, we consider the finitetime control problem of networked system with structural uncertainty and jamming attack. By constructing a new augmented Lyapunov function, the sufficient condition for the finite time stability of the system is explored. By involving linear matrix inequality approach, the sufficient condition is reduced to a feasibility problem which is dependent on network induced delay and the bound of external disturbance. Then, the design strategy of state feedback controller is proposed, which makes the network system more suitable for engineering practice. A numerical example is presented to illustrate the effectiveness of the proposed method.