Drought stress affects the photosynthesis of Osmanthus fragrans Chenghongdangui leaves. The study looked at how different levels of soil water affected the plant's photosynthetic properties. Drought stress reduced the plant's net photosynthetic rate, stomatal conductance, and transpiration rate, but increased water use efficiency. The plant could adapt to high light intensity but was efficient in using lower light intensity. Drought also impacted light and CO2 response curves, with some parameters decreasing and others increasing with increasing drought stress.