This paper presents the design and development of three-dimensional braided honeycomb structures. The basic principles and braiding process are described. The relationship between braiding parameters and honeycomb geometric parameters is established and several three-dimensional (3D) braided honeycomb fabrics are introduced. Based on the principle of the 3D braiding ‘four-step’ method, the interlaced state of yarns can be changed by controlling the movement of yarn carriers, so the separation and combination of the braid can be controlled, then 3D braided honeycomb fabric can be formed. As the number of braiding cycles of wall length increases, the relative density will gradually decrease, but the number of braiding cycles of free wall length has a greater effect on the relative density. When the number of columns of yarns participating in wall thickness increases, the relative density will gradually increase. The relative density also showed a positive correlation with the braiding angle. With the increase of the opening angle, the relative density gradually decreases, although there is a minimum point after which a little increase is observed. This paper provides significant guidance for designing various 3D braided honeycomb structures and evaluating their relative density, and can be a reference for the design and development of new honeycombs structures.