The present study was designed to evaluate and determine the phytochemical composition, antioxidant, anticancer and anticoagulant activities of the aqueous extracts of Acanthus ilicifolius roots and Lumnitzera racemosa leaves from Pichavaram mangrove forest, Tamil Nadu, India based on folklore knowledge. The preliminary phytochemical screening revealed the presence of the following classes of bioactive compounds: phenols, flavonoids, alkaloids, terpenoids, sterols, tannins, carbohydrates, cardiac glycosides, saponins and quinones. The total phenolic content was reported much higher as compared to the total flavonoid content mainly in the leaf extract of L.racemosa. This mostly contributes to the antioxidant power of the extracts, which is affirmed by the IC50 values of the crude extracts in the DPPH assay, which was lower than the ABTS assay. The FRAP assay also exhibited a consistent increase in reducing ability with increase in the concentration which is indicative of the extract’s antioxidant potential. The extracts were also reported to exhibit in vitro cytotoxicity and apoptosis inducing ability in Hep G2 cancer cells. And the anticoagulant study conducted provided a first hand report for the plants exhibiting the property. However, further studies must be conducted for secondary metabolite profiling to decipher and clarify the compound(s) responsible for the reported activities of the plant crude extracts.