We evaluated 17 genotypes of stem amaranth (Amaranthus lividus) in terms of dietary fiber, moisture, carbohydrates, fat, ash, gross energy, protein, minerals, phytopigments, total antioxidant capacity (TAC), vitamins, total flavonoids (TFC), total polyphenols (TPC) and their variations. Stem amaranth leaves have abundant dietary fiber, moisture, carbohydrates, and protein. We found significant amount of potassium, calcium, magnesium (9.61, 24.40, and 29.77 mg g-1 DW), iron, manganese, copper, zinc, (1131.98, 269.89, 25.03, and 1006.53 µg g-1 DW), phytopigments such as chlorophyll a, chlorophyll ab chlorophyll b, (27.76, 42.06, and 14.30 mg 100 g-1 FW), betalain, betaxanthin, betacyanin (62.92, 31.81, 31.12 µg 100 g-1 FW), total carotenoids, beta-carotene (1675.38, 1289.26 µg g-1 FW), vitamin C (1355.46 µg g-1 FW), TPC, TFC (228.63 GAE and 157.42 RE µg g-1 DW), and TAC (DPPH, ABTS+) (26.61, 51.73 TEAC µg g-1 DW) in the leaves of stem amaranth. Genotypes exhibited a wide range of variations. Three genotypes DS40, DS30, and DS26 could be used as an antioxidant profile enriched stem amaranth. Phenolics, phytopigments, flavonoids, and vitamins of stem amaranth leaves exhibited strong antioxidant activity. Stem amaranth could be a potential source of dietary fiber, moisture, carbohydrates, protein, minerals, phenolics, phytopigments, flavonoids, and vitamins in our daily diet for attaining nutritional and antioxidant sufficiency.