Herbal medicines are gaining attention day by day and Solanum nigrum is one of the traditional medicinal plants used in ethanobotanic systems throughout the world. These plants have been traditionally used as an analgesic, antiseptic, antidysentric, tonic, laxative, anticancer and antiulcer etc. Locally available taxa of Solanum nigrum Complex were investigated to determine their medicinal, nutritional and antioxidant values and evaluate their chemotaxonomy. GC-MS analysis of the n-hexane-extracts showed the presence of Squalene, Phytol, Palmitic acid, Linolenic acid, ester of Palmitoleic acid along with a variety of hydrocarbons as the chemical constituents. Solanums are famous for alkaloids. Several glycoalkaloids (Solasonine, α-Solamargine, β-Solamargine and α- Solanine) and their aglycones (Solasodine and Solanidine) were analyzed by HPLC and GC-MS. Flavonoids are secondary metabolites that are powerful antioxidants. Total flavonoid contents in the taxa were determined by two complementary colorimetric methods. Glycones and aglycones of Quercetin were examined that had been reported to be valuable medicinally active compound.