This paper presents a discretization method for the development of a modular morphing wing. The proposed method determines the number of morphing wing modules and their respective spacing required to emulate a known wing shape associated with a particular flight regime/requirement. This method consists of two main steps. The first step is geometry discretization. In this step, curvature and twist distribution from the reference wing quarter chord line are extracted and used to determine the spacing of the discretized wing modules. This is achieved by clustering more, tightly spaced morphing wing modules in areas of large total curvature, and fewer, longer wing modules in areas of small total curvature. By doing so, geometric congruency between the reference and discretized wings is maintained. The second step is for performance evaluation. In this step, an aerodynamic performance index, like the lift-to-drag ratio, for a given flight regime is used to evaluate the effectiveness of each modular morphing wing configuration. Morphing wing modules are sequentially added until an acceptable flight performance is achieved by the discretized wing. The effectiveness of the proposed discretization algorithm is demonstrated through a case study by determining an optimal number of modules for a modular morphing wing.