In this paper, we tested net photosynthetic rate (Pn), stomatal conductance (Cond) and transpiration rate (Tr) of two species of Liquidambar styraciflua and Acer rubrum leaf by using Li-6400 photosynthesis analyzer system. The results showed that the curves of net photosynthetic rate (Pn) of two plants had two peaks. The methods of simple relative analysis and path analysis were used to study the relationship between Pn and multivariate of the two introduced colored leaves plants. The results were as follows. Different types of plants had different Pn influencing factors; Pn influencing factors for Liquidambar styraciflua were Tr, Cond and VpdL, while those for Acer rubrum were Tr and Ci.