Considering the specifically application environment for in-service inspection and maintenance of steam generators, an multifunctional manipulator system was developed first in China. This manipulator can be used in many occasions, such as eddy current inspection of tube, ultrasonic inspection, plugging, sleeving, and television inspection. The manipulator includes a base modular and six rotational joint modules. By modular design, not only the reliability and maintainability of the manipulator are improved, but also the requirements by different SGs are satisfied. The manipulator worked at a special two-base model, which improved the efficiency of services and greatly decreased the levels of radiation.