Abstract: Seeds aqueous extract of Nigella sativa were evaluated for their effect on germination and seedling growth of Vigna radiata. Two different methods were used to prepare the seed aqueous extract. The aqueous extracts prepared were found to affect germination percentage and seedling growth of V. radiata. The germination percentage and seedling growth of V. radiata decreased as the concentration of the seeds aqueous extracts of N. sativa increased. Severe toxicity was observed at high concentrations and moderate toxicity at low concentrations in comparison with water control. Seeds aqueous extract significantly inhibited root length more than shoot. The aqueous dried powdered extract soaked for 4 days with or without boiling had inhibitory effect on germination and seedling growth of V. radiata, but method 2 (with boiling) was the most effective one specially on root length.