The primary structure of the cellular wall of Shanghai Natural History Museum (SNHM) can be defined as a grid structure on a single curved surface (developable), with a cell-like configuration. The shape of the wall (surface) is defined by two free-form curves, which explicate a ruled/lofted surface. The cellular wall is one of the most captivating elements in the SNHM design. Besides its architectural appearance it also has an important function in the structural system to distribute both horizontal and vertical forces. It requires large efforts to create the optimal configuration that meets both its architectural and structural objectives. This includes the structural material of the cellular wall. The objective of this Master’s thesis research is to explore an ‘optimal’ grid structure for the cellular wall. Since the geometry of the wall surface is determined in advance, the design exploration will focus on the grid/pattern generation, and the basic purpose of optimization is to explore a pattern in which elements are tuned up by different design constrains (requirements). The chosen approach is to design the structural cellular wall by parametric CAD modeling via parametric design tools (GenerativeComponents, etc). These parametric associative tools generate the complex geometry by applying rules and capturing relationships among model elements and link the geometrical data to the analytical and drafting software. The typical modeling process and advantages of this approach will be exampled by a case study of Nautilus shell model (Chapter 4.2). Chapter 2-4 will give some background information based on literature study, including the main topics of: SNHM project information and structural optimization proposals, Free-form/Special structural design technologies, and parametric associative design approach. In Chapter 5, the design alternatives will be studied: a design exploration diagram will be draw to clarify the design constrains and their requirements, following the proposal of structural parameters. Various structural materials with construction methods will be compared, and some references study for the structural patterns and grid structures will be recorded. Study of grid structures with basic grid types (rectangular, triangular, hexagonal) will be performed to high-light the structural behaviors and design principles of cell-like grid. In Chapter 6 & 7, cell-like pattern exploration by parametric CAD modeling will be conducted, which includes building parametric CAD models and structural analysis. According to the grid generation technologies (pre-studied in Chapter3), the parametric models will be created in 3 categories: 1- Structured grid models Structured grids have advantages of easy to implement and good efficiency, but various grid sizes can’t be introduced or the grid cells will deform too much. Regular grid will result in un-evenly distributed loads and stresses under the design load cases. 2- Modified structured grid models A- Insert triangular elements, following the stiffness requirement: this method increases the total stiffness and creates moment-free nodes, but at the same time, it's easy to cause stress concentration. B- Locally double-up hexagonal grid, following the strength requirement: The implementation of double-up grid is easier and results in a configuration of fractal geometry (local double rhythm). 3- Unstructured grid models Unstructured grid models are generated via Voronoi Diagram. Some experiments have been done to find efficient methods to generate a point-set (grid points) and generate grid on the wall surface. The ‘attract & repel’ method and UV mapping tool were implemented in this design case. When the local densities of the grid structure are fine tuned up with the imposed load cases (structural requirements), the material will be used in an efficient way, which can be read from the analysis results – better forces distribution and low stress level. The local densities/grid sizes are changed smoothly, which brings nice design aesthetic. [Suggestion] In the modified structured grid models, by locally cutting-out triangles will cause stress concentration, which cannot efficiently increase the total stiffness. A suggested method is to corporate Voronoi diagram with the associated Delaunay triangulation, efficiently getting advantages of the stiff triangle components. Member design Another method is to apply different profiles (crosssections) for individual beam elements according to the structural requirements. Although it will bring extra requirements for construction – carefully coded and stored, this approach provides quite an efficient structure. Chapter 8 concludes the findings of this Master’s thesis research as conclusions and recommendations for further research.