The problem of robust decentralized state feedback stabilization for a class of uncertain switched composite large-scale systems is considered. By using single Lyapunov function technique, sufficient conditions of robust stabilization for uncertain switched composite large-scale systems are obtained respectively. The parameter uncertainties of interconnected subsystems are time-varying and unknown but are norm-bounded. Based on convex combination technique and LMI (linear matrix inequality) method, decentralized state feedback controllers and decentralized switching laws are designed to make the closed-loop systems be asymptotically stable under the assumption that each uncertain subsystem can't be stabilized. The simulation results show the validity of the designed method.