The invention belongs to the field of daily chemicals, in particular to a natural ferment liquid shampoo and a preparation method thereof. The problems of dandruff, hair oil, alopecia, withered and yellow hair and itchy scalps are solved. According to the technical scheme, the natural ferment liquid shampoo is prepared from, by weight, 15-20 parts of ginger, 15-20 parts of tea bran, 15-20 parts of Chinese honeylocust fruit, 15-20 parts of Chinese soapberry fruit, 10-20 parts of radix polygoni multiflori, 10-20 parts of Chinese arborvitae twigs, 15-20 parts of yerbadetajo herb, 5-10 parts of mulberry leaves, 15-20 parts of lemons, 15-20 parts of aloes, 10-20 parts of black beans, 10-20 parts of black sesame seeds, 15-20 parts of shrubalthea leaves, 1-1.5 parts of garden balsam stems, 1-1.5 parts of broadleaf holly leaves, 1-1.5 parts of white mulberry root-bark, 1-1.5 parts of honeysuckle stems, 1-1.5 parts of dried rehamnnia roots, 1-1.5 parts of milkvetch roots, 1-1.5 parts of radix angelica sinensis, 1-1.5 parts of glossy privet fruit, 1-1.5 parts of ginseng, 1-1.5 parts of roots of red-rooted salvia, 1-1.5 parts of ganoderma, 1,200-1,500 parts of washing water of rice, 120-150 parts of brown sugar and 0.01-0.03 part of probiotics. The natural ferment liquid shampoo has the effects of blacking hair, controlling oil, preventing hair loss, generating the hair, removing dandruff, diminishing inflammation, nourishing the hair and making the hair smooth.