Oxygen is life supporting gas and notorious too. It is used by our body for various purposes including for formation of free radicals for different reasons. But, if these free radicals are produced in excess, in spite of free radicals scavenging machinery in our body, they have the destructive property of membrane, DNA, RNA, and proteins. The plants are found to be useful for adding the scavenging ability in our body because of the presence of valuable phytochemicals present in them. Keeping this under consideration, Vachellia nilotica was here studied for determination of phytochemicals present in it and then for evaluation of the antioxidant activity. Not only this, but phytochemicals present in plants can show antimicrobial activity also. Thus, the extract was used to determine the antimicrobial activity in this study. Qualitative study revealed the presence of various phytochemicals such as tannins, flavonoids, terpenoids, saponins, and phenols whereas quantitative study showed the presence of polyphenolic compounds in ample amount. It also showed the significant antioxidant and antimicrobial activity. Thus, the present study demonstrated the potential of V. nilotica to reduce the oxidative stress and to kill the bacteria including gram-positive as well as gram-negative.