A class of hybrid in state systems, which modelled as a finite family of differential equations with parameters uncertainty is considered. Each model of this family describes the individual mode of the system. The transitions between these modes are described by a homogeneous Markov chain. At the moment of mode change (jump of Markov chain) the state vector can be changed discontinuously too. A state feedback control law is obtained, which guarantees both exponential stability in the mean square of closed-loop hybrid system and prescribed H∞ performance for all plant parameters uncertainty and for all transition probabilities matrix uncertainty from the given domains.