Alkaloids are a group of naturally occurring chemical compounds that contain mostly basic nitrogen atoms. This group also includes some related compounds with neutral and even weakly acidic properties. Also some synthetic compounds of similar structure are attributed to alkaloids. In this research, we study the alkaloid containing drugs with Immunomodulator activity. The present study was carried out to investigate morphological, microscopical, physicochemical and phytochemical screening of Piper longum (fruit), Tinospora cordifolia (stem) and Aconitum heterophyllum (root). Morphological studies showed the presence of various diagnostic characters. Inmicroscopical study, T.S of Piper longum fruit shows 6 to 12 fruitlet, stem of Tinospora cordifolia shows uppermost layer of cork, differentiating into outer zone of thick-walled brownish and compressed cells and root of Aconitum heterophyllum shows single layered epidermis consisting of light brown tabular cells rupturing on formation of cork.Ash value, extractive value, foreign organicmatter,moisture content and TLC were determined for quality standard of drugs. The result of the study could be useful for identification and preparation of monograph of the plant.