Background: Fruit juice of Benincasa hispida (BH) is regarded as Vrindamadhava that is recommended for internal use in snake’s bites. The fruits have been reported to contain good amount of proteins, enzymes, Vitamin B1 and C1 flavonoid C-glycoside, terpenes, phenolic acids and free sugars such as glucose, rhamnose, mannitol, uronic acid, astilbin, catechin, naringenin, pectic polysaccharides and even some trace metals. Polyalthia longifolia (PL) has been well known for its ayurvedic preparations such as Sitaphala kula, Kaphapitashama, Anulomak and Krimighna. PL leaves has been reported to contain phytoconstituents like polylongine, Aporphine-Noxide alkaloids, allo-aromadendrene, caryophyllene oxide, β-caryophyllene, β-selinene, α-humulene, α-pinene and camphene. Carissa congesta (CC), known as Bengal currant, have yielded 2-acetyl phenol, carissone, carindone and Des-n-methylnoracronycine. β-sitosterol, an important phytoconstituent recognized from all these selected plants has been well known for its ethnopharmacological importance. In this new study, the research team members has focused on determining the percentage of the β-sitosterol present in the BH seeds, CC roots and PL leaves by subjecting the extract to High Performance Liquid Chromatography (HPLC). Materials and Methods: BH, CC and PL plants were shade-dried and extracted by suitable extraction methods. In HPLC, peaks obtained in the extracts were compared with the standard by matching their retention time. Results: The amounts of β-sitosterol present in the BH seeds, CC roots and PL leaves extracts obtained at 254 nm were found to be 36.00, 7.46 and 3.21% w/w respectively. Conclusion: Thus, BH, PL and CC extracts were said to contain β-sitosterol as a key constituent.