Abstract: In this paper, a new decentralized model reference adaptive control scheme is presented for large scale interconnected systems consisting of subsystems with unknown parameters, bounded disturbances, and nonlinear interconnections. The scheme is applicable to the case where the relative degree n*i of the transfer function of the isolated subsystem can be any value. Based on Lyapunov stability theory, the sufficient condition for the global stability of the decentralized adaptive control system is proved. Compared with other decentralized adaptive control schemes, the scheme presented in this paper is more general and practical because it can be used in the case of n*i >2.