This paper proposes a robust control design based on a new switched robust integral sliding mode (SRISM) for switched systems with unmatched uncertainties. The SRISM is a sliding surface consisting of multiple sliding modes of subsystems and is robust with respect to the structural decomposed unmatched uncertainties. Each sliding mode of the subsystem can suppress the unmatched uncertainties. Their parameters are given by the conditions of linear matrix inequalities (LMIs), and their reachabilities are guaranteed by the sliding mode controllers. Finally, numerical and application simulation results for an inverted pendulum swing-up control are provided to illustrate the validity of the robust control design.INDEX TERMS Switched systems, unmatched uncertainty, sliding mode control, robustness, integral sliding mode.