Abstract: In this paper, the composite stochastic systems with time delays in their low order subsystems are studied in terms of their interconnecting structure by using the box theory. The excitations are assumed to be parametric white noises. By using the vector Lyapunov function method, the exponential string stability about the infinite composite systems with time delays is discussed and the sufficient conditions of exponential string stability for some classes of nonlinear composite stochastic systems are established. The case of exponential string stability for coupling systems with time delays and vehicle-following systems with time delays are considered. The given example shows that the theorem is convenient to be applied in practice.