The invention discloses application of a pentacyclic 
triterpene compound and a 
medicine composition, and further discloses the pentacyclic 
triterpene compound shown in the formula A or the formula B in the specification, and application of a stereoisomer or a 
tautomer or pharmaceutically acceptable salt or solvate or polymorph of the pentacyclic 
triterpene compound in preparing 
medicine for treating diseases (especially 
cancer) caused by 
cell apoptosis or 
cell damage and a BCL-XL inhibitor. R1, R2, R3, R4, R5, R7, R8, R9, R10 and R11 are independently selected from one of hydroxyl, 
hydrogen, 
halogen, COR13, COOR14, C1-C4 alkoxy and C1-C4 
alkyl, and R6, R12, R13 and R14 are independently selected from 
hydrogen or C1-C5 
alkyl. The pentacyclic triterpene compound has higher inhibitory activity on binding between BCL-XL and pro-
apoptosis protein and has guiding significance on design and research and development of the 
medicine.