In order to ascertain the mechanism of nitrogen levels on the photosynthetic system in different tea varieties, we investigated the growth vigor, chlorophyll content, photosynthetic rate and chlorophyll fluorescence parameters in three tea varieties（Fuding dabai tea, Baojing huangjin tea No.1 and Baihaozao) by the pot experiment under nitrogen stress ［(control: N₀(0 g), low nitrogen: N₁(11 g), suitable nitrogen:N₂(22), high nitrogen: N₃(33 g)］. Results showed that：（1） Nitrogen application significantly promoted tea growth, and the chlorophyll content, net photosynthetic rate (P_n), stomatal conductance (G_s), transpiration rate (T_r) increased after nitrogen application, while the intercellular CO₂ concentration (C_i) decreased, of which N₂ treatment had the greatest impact to them. The variation trends of water use efficiency (WUE) in 3 tea varieties were different with each other. （2）After treated with N₂, the primary maximum photochemical efficiency of PSⅡ(F_v/F_m), photochemical quenching coefficient (qP) and the relative electron transport rate of PSⅡ(rETR) also increased most in three varieties, while the nonphotochemical quenching coefficient (NPQ) decreased. (3) The results indicated that there was a correlation between the chlorophyll content and photosynthetic parameters in tea leaves, and it represented a variety specificity between them. In conclusion, nitrogen application could increase the chlorophyll content, G_s and qP, and enhance net photosynthetic rate. Compared with control, the photosynthetic characteristics, chlorophyll fluorescence parameters and WUE showed different characteristics in tea varieties under different nitrogen levels. It indicates that we can rapidly evaluate the needs of nitrogen nutrition in tea plants based on the chlorophyll content, photosynthetic characteristics and chlorophyll fluorescence parameters, and provide guidance for the management of tea plantation.