The effects of salinity on growth of Eucalyptus camaldulensis Dehnh. seedlings were determined salt tolerant ability. Two-month-old seedlings were cultured for 7, 14 and 21 days on Murashige & Skoog (1962) medium supplemented with sodium chloride at concentrations 0, 100, 200, 300 or 400 mM. The seedlings treated with 0, 100 or 200 mM NaCl showed no significant differences in the maximum quantum yield of PSII (Fv/Fm), the quantum yield of PSII (ΦPSII), the net photosynthetic rate (Pn),shoot and root fresh weight whereas the seedlings treated with 300 or 400 mM NaCl for 7 days showed reduction in Fv/Fm, ΦPSII, Pn, shoot and root fresh weights. The Fv/Fm,ΦPSII, Pn and fresh weight of the seedlings exposed to severe salt stress for 7 days were greater than those for 14 and 21 days, respectively. The results indicated that E. camaldulensis seedlings could stand tolerating to 200 mM tolerated moderately salt stress without physiologically photosynthetic disorder and the responses could be evaluated on day seven of salt exposure.