The invention discloses antibacterial plant detergent and a preparation method thereof. The antibacterial plant detergent is prepared from the following formula components in parts by mass: 5-15 parts of nano carbon crystal, 3-5 parts of lemon essential oil, 6-10 parts of shell powder, 15-25 parts of saponin, 6-8 parts of osmanthus essential oil, 5-9 parts of hyssopus officinalis, 6-10 parts of natural latex, 12-14 parts of orange peel, 11-13 parts of egg white powder, 5-7 parts of Chinese soapberry fruit peel, 8-10 parts of artemisia argyi oil, 4-6 parts of tea seeds and 100-300 parts of deionized water. The antibacterial plant detergent does not contain any chemical component, and not only contains components which have a good oil stain washing effect, but also contains a great deal of vitamins and other nutrient elements which are needed by a human body, thus achieving the aims of providing nutrition and protecting the skin while cleaning articles.