Plants have long been a significant source of phytomedicines for human health, so it is important to look into the different phytoconstituents that they contain. The existence of secondary metabolites has a number of pharmacological and biochemical effects, according to the phytochemical study of Amaanthus dubius. Preliminary analyses of Amaranthus dubius with ethanol, methanol, acetone, ethyl acetate, chloroform, and hexane were conducted to identify the following phytocho-chemical extracts: alkaloids, flavonoids, phenols, tannins, saponins, cardiovascular glycosides, steroids, proteins, and carbohydrates. The results of this study indicated that Amaranthus dubius methanol extracts with the highest amount of secondary compounds are essential for human health. The methanolic extract of Amaranthus dubius had reducing activity, but it was lower than L-ascorbic acid, a reference antioxidant, and the extractives increased the reducing activity as the extract concentration increased. Higher absorbance means further reducing strength. The present study revealed that methanolic extract of Amaranthus dubius had significant free radical scavenging potential.