The invention relates to a soapberry in-situ gel preparation for treating candida albicans vaginitis and a preparing method thereof, and belongs to the technical field of gynecological medication. Thepreparing method comprises the steps: preparing a water extraction fermentation concentrate of soapberry, preparing a water extract fermentation liquid with a proper concentration according to the saponin content, and preparing a temperature-sensitive gel from the water extract fermentation liquid, wherein the effective residence time in vagina is ensured. The soapberry in-situ gel preparation has the advantages of simple production, little toxic and side effects, and significant effect against candida albicans, and can avoid the potential drug resistance threat of azole antifungal agents, has wide soapberry sources and convenient material taking.