Abstract: The variable structure control for a class of linear systems with delays in state variables is studied in this paper. It is shown that switching functional should be used for variable structure control systems with delays occuring in state variables, while it is well known that switching function is usually used for systems in which there is no delays in states or in control. The design method for the switching functional which leads to stable sliding modes is presented if the system is spectrally controllable. The variable structure controller is obtained by the use of asymptotic law. The sufficient and necessary condition for the existence of the transformation which can be used to transform a general time-lag linear system into the class of systems discussed in this paper is given.