Saline conditions affect nitrogen (N) assimilation of higher plants. To study the effect of salinity and N source on growth and N uptake in wheat (Triticum aestivum L.), plants were grown in a growth chamber under controlled conditions. The nutrient solution contained 4 mM N, applied as either calcium nitrate [Ca(NO3)2] or ammonium sulfate [(NH4)2SO4], or a mixture of both, and the salinity treatments consisted in two levels of sodium chloride (NaCl) (1 and 60 mM). Salinity significantly reduced shoot and root growth and the effect of the N source was dependent on which salinity treatment was applied. Salinity decreased the net uptake rate of nitrate (NO3) and NO3+ammonium (NH4), but had little effect on NH4 uptake when this nutrient was applied alone. Dark conditions affected NO3 uptake to a greater extent than NH4 uptake. The best N source for wheat growth was a mixture of NO3 and NH4, especially under saline conditions or periods of low irradiance.