This paper focuses on the inspection for sloping dam wall by a remotely operated vehicle (ROV). First, a dedicated ROV for dam inspection is described. Second, a fixed-distance tracking control strategy is proposed to guarantee the fixed camera-to-subject distance in sloping dam inspection, which is instrumental in sonar image fusion for the large-scale dam wall with a certain inclination. In addition, the ROV can periodically surface up and correct its position by using the onboard GPS, such that the positioning accuracy of the ROV and its detected crack point can be improved. Third, in order to reject the unknown hydrodynamic coefficients, water intake and currents, a model-independent fuzzy PI controller is designed for robust tracking in dam inspection. Finally, some numerical and experiment results are given to illustrate its performance.