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Melaleuca linariifolia Sm. (Genus: Melaleuca ; Family: Myrtaceae) cultivated for its ornamental usages in the Kumaun Himalayan region of Uttarakhand is commercially known as flax-leaved paper bark tree. The present study analyzes the chemical variation of the essential oils obtained from aerial parts and flowers of M. linariifolia. The effect of post-harvest shade drying on the essential oil composition was also assessed in the study. Total of 16 compounds accounting for 94.2 % and 94.6 % were identified in the aerial parts and flowers essential oil, respectively. 1,8-Cineole (71.8 %–73.8 %) was identified as the predominant compound in both the studied essential oils followed by limonene (1.7 %–9.3 %) and α-terpineol (4.2 %–6.7 %). Moreover, the fresh aerial parts had 73.8% of 1,8-cineole content which increased up to 79.2% post-harvest drying. The study revealed oxygenated monoterpenes as the major class constituents with 1,8-cineole as the marker component ranging from 67.7 % to 79.2 % during the post drying analysis. While assessing the biological activities, the antioxidant activity of the oils was investigated in vitro using three assays: DPPH radical scavenging activity, Iron(II) complexing activity, and H 2 O 2 radical scavenging activity. The oil also inhibited the activity of α-amylase with IC 50 of 3.26 ± 0.04 μg/ml and protein denaturation with IC 50 of 3.0 ± 0.03 g/ml. This is the first-time report of essential oil analysis of M. linariifolia flowers and post-harvest drying study from bhabar region of the Kumaun Himalayas. The high essential oil yield, rich chemical composition and biological activities suggest the cultivation of Melaleuca species as an industrial crop. [Display omitted] • The flowers of Melaleuca linariifolia show high essential oil yield than aerial part (leaves + stem) of the plant. • Chemical composition of essential oil of Melaleuca linariifolia was analyzed by using GC-FID and GC-MS techniques. • Post harvest shade drying results increase in percentage concentration of marker compound 1,8-cineole upto 79.2%. • Biological activity analysis confirms potent in-vitro antioxidant, inhibition of α-amylase, and inhibition of protein denaturation activities in essential oil. • This study provides a directive for development of high yielding and commercially benign species of Melaleuca linariifolia. [ABSTRACT FROM AUTHOR]