The present study deals with the pharmacognostic and phytochemical studies of leaves of Thespesia Populnea Linn. The objective of the present work comprise of collection, identification, microscopical and phytochemical evaluation of leaves of Thespesia Populnea Linn. The preliminary phytochemical studies indicates the presence of alkaloids, flavonoids, carbohydrates, phytosterols, tannins, saponins, proteins and aminoacids, terpenes, phenols, gums and mucilage’s. The sections were taken and cellular structures were studied. The T.S of leaf shows the presence of epidermis, vascular bundle, glandular trichomes which are peltate type, cleared leaf showing vein-islet, vein-termination and mucilage masses, Peeling of the lamina showing abaxial epidermis- with stomata .Powder microscopy of the leaf shows the presence of crystals in the peltate scale, crystals in the ground parenchyma and phloem cells.