Medicinal plants have bioactive compounds which are used for curing of various human diseases and also play an important role in healing. Phytochemicals have two categories i.e., primary and secondary constituents. Primary constituents have chlorophyll, proteins and amino acids. Secondary constituents contain terpenoids, flavonoid, glycoside and alkaloids. This paper deals with Phytochemical studies of Trifolium pratense, Astragalus corrugates and Hypericum perforatum. Phytochemical tests were carried out to know about the qualitative existence of secondary metabolites in them. For the current article screening of alkaloid, flavonoid, glycoside, saponin, tannin, terpenoid and have been carried out.