Abstract: To study the effects of nitrogen, phosphorus and potassium fertilizers on photosynthetic characteristics of‘Yuluxiang’pear, taking 10- year- old‘Yuluxiang’pear trees as the study objects, we measured the net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Cs), intercellular CO2 concentration (Ci), water use efficiency (WUE) and chlorophyll content (Chl) after applying nitrogen, phosphorus and potassium fertilizers by using the portable photosynthesis determinator and chlorophyll meter. The results showed that: Pn, WUE and Chl in pear leaves after the nitrogen and phosphorus fertilizer treatment significantly increased, while Tr, Ci and Cs of the nitrogen fertilizer group significantly reduced; Pearson analysis showed a positive correlation between the application amount of nitrogen, phosphorus fertilizer and Pn, WUE, Chl, and a negative correlation between nitrogen fertilizer and Cs and Tr suggested that nitrogen might reduce the loss of leaf moisture by affecting Cs, reducing the Tr of the leaves; no significant differences between the control and the potassium fertilizer group were observed. In conclusion, the nitrogen and phosphate fertilizers could significantly increase the water use efficiency, promote the synthesis of chlorophyll, and improve the photosynthetic production efficiency in leaves of‘Yuluxiang’pear.