Summary: Based on Lyapunov stability theory, a typical adaptive control system with dead zone is first proposed for a class of nonlinear plants with bounded disturbance. It is shown that a larger state tracking error norm is given when a conservative dead zone value is set to achieve a stable adaptive control scheme for the plant subjected to a bounded disturbance. To solve this problem, a modified adaptive control with dead zone scheme is proposed. The proposed adaptive control scheme is proved to be stable and the state tracking error norm can be reduced.