At the fast-changing modern era, life styles are tending to emphasize on both high renewing rate and the sense of beauty, especially in the Eastern world. In response to it, we focused on designing a furniture that meets the modern life style. “Spiral Stool” is designed with the idea of creating structural module with only cardboard material, which is recyclable and sustainable. The rotated squares on top and bottom create unique fractal elevation that reflects lights in different angles. Both children and adults can use the Spiral Stool while kids can even paint on it, which can also use as modular units to configure as a low table. Due to its structural system and using neither hardware nor glue, the most challenging aspect of designing Spiral Stool is the precise dimension and accurate manufacturing. Inspired from the ancient wisdom, we adopted a way which is mortise and tenon joint alike, let eight pieces of cardboard sheets connect with each other vertically, so that the Spiral Stool can stand the weight at the maximum of 100 kilograms. A few prototypes are created to test the joint and the tolerance of cardboard material. The structure becomes weak when the joint gap exceeds 1 mm. The dimension and design change happened a few times to achieve perfect fitting with fine-tuned detail and precisely manufactured pieces. With the belief in sustainability and creativity, we hope to provide an environmental friendly furniture with the sense of beauty to modern living.