Abstract: The cuttings of Yunnan purple Bougainvillea spectabilis with healthy growth and consistent growth were used as experimental materials, one group of shading was set and the other group under natural lighting conditions was adopted, the effect of shading on the growth and development and photosynthetic physiology of Yunnan purple Bougainvillea spectabilis was studied, in order to provide reference for the cultivation and management of Yunnan purple Bougainvillea spectabilis.The results showed that under shading conditions, plant height growth, chlorophyll content, leaf morphological index value, root activity, soluble sugar content and enzyme activity were all greater than those under light conditions, while plant ground diameter growth, flowering number, the net photosynthetic rate and intercellular CO₂ concentration were lower than the light conditions, and there was no significant difference in stomatal conductance and transpiration rate.In general, from May to September, the shading treatment of Yunnan purple Bougainvillea spectabilis was beneficial to the growth of plants, while the light treatment was beneficial to the flowering of Yunnan purple Bougainvillea spectabilis.