The main objective of the present study was to assess the effect of cold and hot Nigella sativa seeds aqueous extracts (NSSCAE and NSSHAE, respectively) and Nigella sativa seeds crude powder (NSSCP) on germination, some growth parameters and chemical constituents of Lupinus termis L. in mixed cropping system. Proximate analysis of Nigella sativa seeds showed that it contains oil, crude protein and ash beside significant amounts of vital mineral elements. The germination percentage was notably decreasing with increasing the concentrations of NSSCAE and NSSHAE. The effect on hypocotyl (HL) and radicle lengths (RL) of L. termis seeds was highly recognized. The applied concentrations of NSSCP caused a significant decline in growth parameters of L. termis. In addition, there was an inverse proportional relationship between increasing NSSCP concentrations and chlorophyll a and b, carotenoids and total pigment content of leaves. The variation in some biochemical constituents of L. termis seeds as affected by different concentrations of NSSCP was documented. The study concluded that seeds of Nigella sativa adversely affect seed germination and seedling growth of L. termis.