The norm Type-2 fuzzy set is defined and its representation based on the structured element is introduced, and an exact computation method is provided for the centroid of the norm Type-2 fuzzy set.When the secondary membership function can be expressed by the linear representation of structured element, an approximation method is provided for the centroid of the norm Type-2 fuzzy set.The examples of comparing the exact computational results with the approximate results are given, which show that the proposed methods are computationally simple and have a wide rang of applications, and under certain conditions, the approximation solution and the exact solution fit well.