The invention provides application of gamabufotalin and a salt compound thereof in preparation of a medicine for treating gynecological tumor. By comparing in vitro anti-cancer experiments of a bufadienolide extract and monomeric compounds, namely the gamabufotalin, cinobufagin, bufalin and bufotalin as well as hydrochlorides or sulfates of the four compounds to four gynecological tumors, namely human ovarian cancer cells A2780, human ovarian cancer cells SK-OV-3, human cervical carcinoma cells and human endometrial cancer cells, an experimental result shows that the gamabufotalin has stronger activity against gynecological tumor cells than the bufadienolide extract and the monomeric compounds, namely the cinobufagin, the bufalin and the bufotalin, and the hydrochloride or the sulfate of the gamabufotalin has stronger activity against gynecological tumor cells than the hydrochlorides or the sulfates of three compounds, namely the cinobufagin, the bufalin and the bufotalin. The gamabufotalin and the salt compound thereof provided by the invention have the advantages of clear components, controllable quality, strong anti-cancer activity, and small adverse reaction, and are expect tobe developed into a novel anti-cancer drug.