Extract tea saponin from tea seed cake and add it to natural soap base made of coconut oil, tea seed oil, palm oil, supplemented by metal chelating agent EDTA-2Na, glycerin, spices, deionized water, etc. The auxiliary agent is heated and stirred, put into the mold, and cooled down to make soap. The prepared tea saponin soap has good decontamination performance, rich foam and hard soap, and has good application prospects.