This paper explores the issues in the structural design of Mecanum wheels. We analyze the geometric characteristics of the Mecanum wheel rollers and explain the principle of the formation of the roller generatrix. Based on this, a mathematical model is established, and the parametric equation of the roller generatrix is successfully derived. Since the roller generatrix is a spatial curve and cannot be directly used for the construction of the roller profile surface, we also elaborate on the calculation methods and steps for the roller meridian. Examples of generating the roller meridian and its profile surface in Matlab are provided. Additionally, this paper analyzes a commonly used approximation method for the roller generatrix, introduces the process of constructing the roller profile surface using this method, and conducts an error analysis of the approximation effect, discussing the feasibility of manufacturing rollers using this method.