A hydroponic experiment was conducted in a greenhouse to estimate the effect of different levels of nitrogen applied on gowth and photosynthetic characteristics of a local salt resistance variety - Cuom and an improved salt tolerance - A69-1 at tillering stage. Rice plant was transplanted in Yoshida nutrient solution with salt treatment including 9 mM MgSO4, 18 mM Na2SO4, 1 mM MgCl2 and 12 mM CaCl2 which was similar to salinity level in coastal soil in Vietnam. Three levels of nitrogen were applied in Yoshida solution such as N1 (1.425 mM). N2 (2.850 mM) and N3 (4.275 mM). The experimental result showed that at 21 days after transplanting (DAT), as increasing nitrogen level from N2 to N3 both photosynthetic rate and stomatant resistance were significantly increased in Cuom variety, but not significant in A69-1 variety. Both total leaves area and plant dry weight decreased in A69-1 variety, whereas they were stable in Cuomo However, from 21 DAT to 28 DAT at high level of nitrogen, both photosynthesis and proline accumulation decreased in Cuom more than that in A69-1.