Abstract: Since the dynamics of unmanned underwater vehicle (UUV) is with properties of high nonlinearity and uncertainty, a robust tracking control method based on error space theory was proposed to deal with the complex marine environment and variation of parameters or module configuration. The error space system including the dynamics of reference platform and tracking errors was constructed, where the error variable is the error between the state of reference platform and UUV that act as state variables of state space. Taking account of sea wave disturbance, simulations were performed to validate the robustness of depth tracking control algorithm. Results show that the tracking accuracy and tracking capacity of the system are improved with robustness enhanced obviously.