The invention relates to the technical field of veterinary medicine, and discloses a formula and a preparation method for killing ascarid in a pet cat, comprising the following raw materials in partsby weight: black plum 10-25g, liquorice 4-8g, Sichuan pepper 3-8g, coptis chinensis 6-10g, chicken 22-29g, skim milk powder 10-17g, mung bean 20-28g, carrot 5-10g, bone meal 5-10g. The invention relates to a formula for killing ascarid in a pet cat and a preparation method thereof, through black plum, Glycyrrhiza uralensis Fisch., Sichuan pepper and Coptis chinensis Fisch. prescription of Chinesemedicine, killing ascarids in pets and cats is a gentler way to kill them, Reduce damage to kittens, effectively kills ascarids in pets and cats, radical treatment of the lesion, black plum are excited about ascarid, Stimulating ascarid retrogression, black plum can effectively kill ascarid in pet cat, and black plum contains tea acid can promote intestinal peristalsis, can effectively discharge ascarid into the body of pet cat kitten, licorice can be used to treat diarrhea, prevent pet cat kitten diarrhea dilution for a long time, reduce injury to pet cat kitten.