This work was carried out in the laboratory of Botany in the College of Sciences in the University of Hail, Saudi Arabia. It deals with the germination conditions of Nigella sativa, used for medicinal purposes for centuries, both as an herb and pressed into oil, in Asia, Middle East and Africa.The germination requirements Nigella sativa, were studied under control conditions in the laboratory. Treatments included four light levels (0 :24) ; (6: 18) ; (12 : 12) then 24 :0) hour ( light : dark) period, six salinity concentrations (0, 2, 4, 6, 8, and 10 gl/L NaCl), and four temperature regimes (15°, 17°, 20° and 25°), using a completely randomized block design.This work shows that germination of Nigella sativa was very sensible to temperature with an optimum of 23°C. Germination will stop below 15°C and after 25°C. For salinity the best seed germination of all experiments was obtained in a distilled water control. The progressive increase in salinity, until 8g/l, have no significant effect on germination. The inhibition of germination was significant only after 10g/l. The absence of light give the best rate of germination that would be lower if light period increase and it will be inhibited completely at 18h of light regime. In this work optimal conditions for germination of Nigella sativa were determined.