The essential oil in the fresh leaves of Rhododendron lepidotum Wall. ex D. Don was isolated using Clevenger-type hydrodistillation apparatus and its chemical compositions were analyzed by GC-MS analytical method. A total numbers of 21 chemical constituents were identified and quantified occupying 96.68% of total oil composition. The chemical constituent of Rhododendron oil composes of monoterpene hydrocarbons, oxygenated montoterpines and sesquiterpine hydrocarbons. The major chemical constituents were α-pinene (39.35%) and β-pinene (13.82%) along with trans-caryophyllene (9.79%), δ-cadinene (9.4%), β-myrcene (7.25%) and α-amorphene (3.77%). The antioxidant activity of Rhododendron lepidotum oil was studied based on DPPH (1,1-diphenyl-2-picryl-hydrazyl) radical scavenging activity by finding IC value and comparing its IC value with standard ascorbic acid. IC value associated with it was 12.22 μg/ml which is nearly closer with standard ascorbic acid (4.42μg/ml) indicating that the fresh leaves of Rhododendron lepidotum essential oil shows good potential antioxidant activities.