A use of an extract of Bombax malabaricum DC. in the manufacture of a medicament for treatment of osteoarthritis is disclosed. The extract of Bombax malabaricum DC. is extracted by water at 115-125℃, 0.35-0.5 Kg/cm2G for 1.5-3 hours.一種木棉花水萃物的用途,係用以製備治療退化性關節炎的藥物,其中,該木棉花水萃物係以水作為一萃取溶劑,於115~125℃之溫度、0.35~0.5Kg/cm2G之壓力下萃取一木棉花樣品1.5~3小時所獲得。