This paper deals with the problem of sliding mode control (SMC) for a class of nonlinear uncertain stochastic systems with Markovian switching. By introducing some specified matrices, the connections among the designed sliding surfaces corresponding to every mode are established. Furthermore, the present sliding mode controller including the transition rates of modes can cope with the effect of Markovian switching. By means of linear matrix inequalities (LMIs) with equality constraint, sufficient conditions are derived such that the sliding motions on the specified sliding surfaces are stochastically stable with gamma-disturbance attenuation level. Finally, a numerical example is given to illustrate the applicability of the present method. (c) 2007 Published by Elsevier Ltd.