The invention discloses a radix puerariae traditional Chinese medicinal preparation for treating acute colitis and a preparation method thereof. The radix puerariae traditional Chinese medicinal preparation is prepared from the following raw materials in parts by weight: 190-210 parts of radix puerariae, 90-110 parts of coptidis rhizoma, 50-70 parts of yam, 70-90 parts of radix scutellariae, 50-70 parts of wrinkled giant hyssop, 100-120 parts of wild chrysanthemum flower, 60-80 parts of radix paeoniae alba, and 80-100 parts of honey, and is prepared by the following steps: firstly slicing and drying the radix puerariae and the yam, mixing the radix puerariae slices and the yam slices with the other medicinal materials, adding distilled water in the mixed materials to be decocted, adding the honey in the decocted liquid, cooling the liquid, then carrying out fine filtration and disinfection by ultraviolet light, metering the liquid in vacuum, and filling the liquid in bottles to obtain the product. The radix puerariae traditional Chinese medicinal preparation disclosed by the invention has the function of diminishing inflammation and resisting against bacteria, can play a good inhibitory function on treating Escherichia coli and shigella dysenteriae and other gastrointestinal bacteria, can be combined with other effective drugs for treating the acute colitis to effectively treat the acute colitis, and is simple and reasonable in preparation technology, low in cost, simple in the medicinal materials and good in the curative effect.