For the purpose of inspecting workpieces or equipments under severe environment, remote ultrasonic testing is of great significance to realize online inspection for processing products or vital equipments. The key problem to apply the remote ultrasonic testing is to keep the stability of the control system for the scanner. Therefore, how to eliminate the uncertain effect of time delay to keep the stability of the control system is the main difficulty in the online ultrasonic testing process. This paper proposed a slide mode approach to realize the position and attitude control for remote ultrasonic scanner. The implement of sliding mode controller with uncertain time delay, the solution of sliding surface and control function are studied. With the dynamic model of the scanner, the controller system is established according to the analysis of the control approach. The simulating results of the system proved the proposed sliding mode control method satisfies the requirements of stability for the remote control system.