Lygeum spartum L. (Poaceae) is one of the most important perennial grass species in arid steppes of Algeria. Its germination responses to environmental stresses are poorly understood. Therefore, experiments were conducted to determine the effect of salinity and temperature on the germination of seeds. Seeds were germinated at three alternating temperatures (10-20, 15-25, and 20-30°C), with four NaCl concentrations (0, 50, 100, and 150 mM) and 12-h photoperiod. Results indicate that seeds can germinate at high salt concentrations (150 mM NaCl). However, highest germination was obtained in distilled water. Lower thermoperiods promoted germination, while high temperatures significantly inhibited the germination of seeds at all NaCl concentrations tested. Rate of germination decreased with increases in salinity. Seeds recovered after being transferred to distilled water, and recovery was higher from higher salinity concentrations and lower thermoperiods. L. spartum is moderately salt tolerant at germination stage, and tolerance is affected by the interaction of temperature and NaCl concentration.