The invention discloses a compound Chinese herbal medicine preparation for treating black mouth disease of sea urchin. The compound Chinese herbal medicine preparation is prepared from the following raw materials in percentage by weight: 30 to 35 percent of honey suckle, 10 to 12 percent of rhubarb, 14 to 18 percent of astragalus root, 5 to 9 percent of common andrographis herb, 5 to 9 percent ofChinese angelica, 5 to 9 percent of campanumaea pilosula, 5 to 9 percent of liquorice, 5 to 9 percent of largehead atractylodes rhizome, and 5 to 9 percent of nutgall. After the compound Chinese herbal medicine preparation is decocted with water, the compound Chinese herbal medicine preparation is used for a medicated bath for the black mouth disease of sea urchin, or sprinkled into a whole pond,and the components are reasonably collocated; and the compound Chinese herbal medicine preparation has the advantages that: the raw materials accord with the formula principle of Chinese herbal medicines, and the compound Chinese herbal medicine preparation enhances the medicinal effect, has no toxin on the sea urchin, does not influence the normal life of the sea urchin, has obvious effect of killing pathogenic bacteria in the sea urchin, can repair spine-falling and black spot lesion parts of the sea urchin, and has the cure rate of over 70 percent; the compound Chinese herbal medicine preparation can be degraded under natural conditions, does not have any toxic or side effect, and has no residue in the sea urchin; the compound Chinese herbal medicine preparation is small in dose and convenient to use; and the raw materials are stable in sources and low in prices, and the production process is simple.