The invention belongs to the field of pharmaceutical preparations, and particularly relates to a gemma agrimoninae suppository and a preparation method thereof. The gemma agrimoninae suppository is prepared by taking gemma agrimoninae fluid extract as a main medicine component and hydroxypropyl methyl cellulose as a penetration enhancer. The gemma agrimoninae suppository is prepared from gemma agrimoninae fluid extract, hydroxypropyl methyl cellulose, glycerol, gelatin and a preservative, and the weight percentage of the gemma agrimoninae fluid extract to the gemma agrimoninae suppository is as follows: 5.0%-5.5% of the gemma agrimoninae fluid extract, 0.5%-2.5% of the hydroxypropyl methyl cellulose, 60%-70% of the glycerol, 20%-30% of the gelatin, 0.075%-0.1% of the preservative and the balance of water. The weight ratio of the gemma agrimoninae fluid extract to the hydroxypropyl methyl cellulose is 10: (0.5-5). The hydroxypropyl methyl cellulose is one or more selected from the group consisting of HPMC-E5, HPMC-E50, HPMC-K4M, HPMC-K15M and HPMC-K100LV, and the hydroxypropyl methyl cellulose is one or more selected from the group consisting of HPMC-E5, HPMC-E50, HPMC-K4M, HPMC-K15M and HPMC-K100LV. The gemma agrimoninae suppository has the advantages of simple formula, simple preparation process, stable drug release speed, no release degree reduction caused by crystal precipitation after drug release, facilitation of drug permeation, and full play of the curative effect of the drug.