Fluctuations in environmental circumstances with varying altitudinal gradients account for variations in plants. This study was performed to scrutinize the impact of varying altitude on medicinal plant, namely, Justicia adhatoda L. for 2 consecutive years. The phytochemical, physicochemical constituents, and morphological aspects of Justicia adhatoda L. were studied and statistically compared. Significant variations were observed among plant height, crown spread, branches, leaves, inflorescence, carbohydrates, phenols, flavonoids, total sugar, and reducing sugar across different elevational sites where the observed variations showed that Justicia adhatoda L. plant chemically adapted itself to sustain at high altitudinal sites by exhibiting change in its phytochemical and morphological aspects. The quality and therapeutic efficacy of medicinal plants are influenced by their biochemical composition, which, in turn, depends on the environment in which they grow. The various biotic and abiotic stresses operating in the environment across altitudinal gradient undeniably perform as a driving force behind these variations and ultimately the survival of medicinal plants. The assessment of biochemical composition of medicinal plants growing at different elevational sites can contribute to selecting the best genotype and better altitude for commercial cultivation of medicinal plants.