Background: During macrofungal inventorisation from an unexplored subalpine forest of Sikkim Himalayas, a new edible mushroom, Ramaria subalpina was found and documented in consultation with the forest dwellers. Objective: The aim of the present study was to understand the antioxidative potentiality and bioactive constituents of a novel taxon, Ramaria subalpina, that is highly prized by the ethnic people of subalpine Sikkim Himalayas, India, for its flavor, texture and gastronomic delicacy since time immemorial. Methods: Chemical composition and antioxidant properties of methanolic extract of dried basidiocarps were assessed using HPLC and several in vitro assay systems. Results: Methanolic extract had phenolics in highest amount, among which pyrrogallol was identified. It also showed potent antioxidant activity. Conclusion: The present study suggests that Ramaria subalpina has strong medicinal prospects. This novel mushroom can safely be added to the world’s edible mushrooms list.