Nigella sativa (N. sativa) (Family Ranunculaceae) is a widely used medicinal plant throughout the world. It is very popular in various traditional systems of medicine like Unani and Tibb, Ayurveda and Siddha. Seeds and oil have a long history of folklore usage in various systems of medicines and food. The seeds of N. sativa have been widely used in the treatment of different diseases and ailments. In Islamic literature, it is considered as one of the greatest forms of healing medicine. It has been recommended for using on regular basis in Tibb-e-Nabwi (Prophetic Medicine). Nigella sativa and its constitutions including some isolated compounds are the potential sources of remedies of varieties of ailments such as antioxidant, anti-inflammatory, antibacterial, antifungal, antiparasitic and antiprotozoal, antiviral, cytotoxic, anticancer, neuro-, gastro-, cardio-, hetapto- and nephroprotective activities. In addition, the N. sativa implies beneficiary effects on reproductive, pulmonary and immune systems along with diabetes mellitus (DM), fertility, breast cancer, dermatological complications, dehydration, dyspepsia, osmotic balance and so on. Among the other isolated chemical moieties, thymoquinone (TQ) is a good target for its potential antimicrobial, antimicrobial, anti-inflammatory, chemopreventive, antitumoral and other activities. N. sativa has got the place among the top ranked evidence based herbal medicines. This is also revealed that most of the therapeutic properties of this plant are due to the presence of thymoquinone which is major bioactive component of the essential oil. The present review is an effort to provide a detailed survey of the literature on scientific researches of pharmacognostical characteristics, chemical composition and pharmacological activities of the seeds of this plant.
 Keywords: Nigella sativa, Miracle herb, Ranunculaceae, Habat-ul-Sauda, Thymoquinone, Tibb-e-Nabwi, Black seeds, Anti-diabetic, Antioxidant