Disclosed is a cucurbitane-triterpenoid for activating estrogen receptor, and a pharmaceutical composition, use and extraction method thereof. The compound is presented as formula (I):wherein a single or double bond is formed between C5 and C10, a single or double bond is formed between C8 and C9； while a single bond is formed between C5 and C10, R1is -O-； while a single bond is formed between C8 and C9, R2is -C=O, -CH(OH),or -CH(OCH3)2； while R1is -O- and R2is -C=O, or -CH(OH), a single bond is formed between R1(-O-) and C19. Meanwhile R1+ R2form γ-lactone, hemiactal or actal.本發明揭露一種葫蘆烷型三萜類化合物、醫藥組成物、用途及其萃取方法，該化合物係如式(I)所示：其中C5和C10之間形成單鍵或雙鍵，C8和C9之間形成單鍵或雙鍵；其中C5和C10之間形成單鍵時，R1係為氧；其中C8和C9之間形成單鍵時，R2係為羰基、甲羥基、甲醛基或甲基二甲氧基；其中R1為氧且R2為羰基或甲羥基時，R1之氧與R2的C19形成單鍵，R1+R2=戊內酯或半縮醛環。
