Andrographis stenophylla C. B. Clarke., (Acanthaceae) is an erect glabrous undershrub with very narrow leaves and stems from a stout rootstock, the corolla pale with dark red stripes. The plant grows in hills of about 1200 meters height in South India. No scientific work reports are available with regard to this plant. The present study, thus deals with the detailed pharmacognostical evaluation of the plant A. stenophylla using light and confocal microscopy, WHO recommended physico-chemical determinations and authentic phytochemical procedures. The physico-chemical, morphological and histological parameters presented in this paper may be proposed as parameters to establish the authenticity of A. stenophylla and can possibly help to differentiate the drug from its other species.