The invention discloses a fermented traditional Chinese medicine detergent and a preparation method thereof. The fermented traditional Chinese medicine detergent comprises an extracting solution of the following raw material components in parts by weight: 95-105 parts of tea seed powder, 95-105 parts of saponin powder, 95-105 parts of soapberry powder, 18-22 parts of cacumen biotae, 18-22 parts of angelica, 18-22 parts of ginseng, 9-11 parts of astragalus membranaceus, 18-22 parts of folium mori, 0.01-0.03 part of chitosan, 0.01-0.03 part of cinnamon powder, 0.01-0.03 part of probiotics and 550-650 parts of cocoon silk glue cooking water. The preparation method comprises the following steps: cooking the cocoon silk glue cooking water to slight boiling, sequentially adding the tea seed powder, the saponin powder, the soapberry powder, the cacumen biotae, the angelica, the ginseng, the astragalus membranaceus, the folium mori and the chitosan, stirring, adding the probiotics and the cinnamon powder when the temperature is lower than 50 DEG C, uniformly mixing, sealing, fermenting at normal temperature for 6 months, or heating up to 35-50 DEG C, fermenting for 0.5-2 months, filtering, adding preservatives and a foaming agent, uniformly mixing, and bottling to obtain a fermented traditional Chinese medicine shampoo product.