Gray sculpture is also called gray plaster in folk culture. It is a kind of architectural decoration art. It was most popular in the Ming and Qing dynasties, especially in ancestral halls, temples, monasteries and mansions of wealthy families. Gray sculpture works of the Qing Dynasty can be seen everywhere in Chen Clan Ancestral Hall and Foshan Ancestral Temple. The craftsmanship of gray sculpture is relatively delicate. It uses lime to sculpt on buildings. The forms of expression include multi-layered "three-dimensional" gray sculpture, relief-style "half-sunken and floating" gray sculpture, and round-carved single-shaped "single" gray sculpture. Multi-layered three-dimensional gray sculpture has high requirements and great difficulty. It uses open-edged tile tubes and copper and iron wires as the torso, tendons and limbs, and uses grass root gray or paper tendon gray to shape a single object in three dimensions. In particular, the head of the character must be finely carved, and then relief or through-carved background decorations are molded on the wall, and finally a single three-dimensional sculpture character is installed. Its characteristics are exquisite and transparent, clear layers, and prominent themes. The semi-sunken and floating plastering process is a little simpler. The method is to first hammer iron nails on the wall, paste the shape, and then the last process is painting. The colors should be bright and eye-catching. Plaster decoration is mostly high in the building, so the painting lines should be thick and strong, the color blocks should be large, strong and clear, and special attention should be paid to the upward viewing effect, so that people standing on the ground looking at it feel comfortable and natural.