Severe health conditions can result from lack of knowledge on the bioactive constituents of medicinal plants, as it the main stay of treatment and prevention of diseases in our locality. Hence, the need to examine the therapeutic active ingredients responsible for plants medicinal ability for better health management. This study analyses the phytochemical constitutes and anti – oxidant activity of the bark of lawsonia inermis. Lawsonia inermis bark was collected, cut into pieces and dried at room temperature. The dried sample was pulverized into fine particle. 200g of the pulverized sample was weighed into a 750mL container and was added 300mL absolute ethanol, then allowed to stand for extraction. The solute obtained by evaporating the ethanol was screened for the presence of phyto – components and the result shows alkaloids, glycosides, saponins, phenols, flavonoids, proteins and amino acid as bioactive substances. Also, lawsonia inermis bark displayed an efficient free radical scavenging potential as the anti – oxidant ability showed the percentage KMnO4 radical scavenging activities of 41.4% which shows close competence with the standard ascorbic acid; 47.9% at EC50; This indicate lawsonia inermis bark to exhibit a good potential as antioxidant and could scavenge free radical from the body. The presence of the bioactive substances signifies its usefulness in therapeutic health as agent that could inhibit diseases causing several ailments and as well be a good source for health management control.