Leaf pattern decoration on black glaze porcelain in High temperature,a cultural symbol combining elegance and aesthetic features, has gradually become a favored ceramic utensil in Chinese tea ceremony culture because of its unique decorative effect. However, its blending technology is still mysterious, and its formation and mechanism have not been fully disclosed under the continuous attention of scholars. Therefore, the mechanism of black glaze color and leaf pattern was revealed by using an experimental simulation method combined with spectroscopic analysis technology, and the relationship between glaze micro-structure and black glaze color was observed and analyzed by using sample hue angle h°, saturation C*, reflection spectrum curve and ultra-depth of field microscope. Based on traditional black glaze, a group of optimum glaze firing parameters was screened out, in which the Si/Al molar ratio was 10.14~10.47, MgO molar amount was 0.19~0.22, CaO molar amount was 0.42~0.47, and glaze thickness was 0.7~0.9 mm, which made black glaze show the most stable color and clarity, and leaf pattern decoration was ideal. The results show that the reasonable composition of glaze and glaze thickness is very important for the color presentation of black glaze and the clear decoration of the leaf pattern. At the same time, the spectroscopic analysis method and experimental simulation method adopted in this paper can effectively assist the research and development of glaze formula optimization in the ceramic industry, which is expected to improve the refinement and intelligence level of the porcelain-making process. At the same time, it realizes the analysis of microstructure and reflection spectrum curve characteristics of leaf pattern decoration on black glaze porcelain, highlights the application prospect of spectroscopic analysis method in the research and development of ceramic clay glaze, promotes the development of ceramic culture, and provides theoretical support for the protection, inheritance, and development of precious cultural heritage. It has important practical application value.