The present invention relates to the technical field of medical dressings, in particular to a medical biological urinary hydrogel functional dressing and a preparation method thereof. The medical biological urinary hydrogel functional dressing is composed of the following raw materials in percentage by weight: glycerin, chitosan quaternary ammonium Salt, peppermint extract, polyhexamethylene guanidine, Solanum nigrum extract, Akebia extract, gardenia extract, Qumai extract, talc powder, Kochia chinensis extract, Tianjihuang extract, Commelina extract liquid, light bamboo leaf extract, and the balance of purified water. The medical biological urinary hydrogel functional dressing of the present invention has little irritation, no toxic and side effects, safe use, good permeability, good curative effect, can give full play to the drug effect, has a long duration of action, and is not easy to relapse. When used in the anus, it directly penetrates into the prostatic body through the anal wall membrane, and can be widely used in the treatment of prostatitis, chronic benign prostatic hyperplasia, abscess caused by hypertrophy, urgency, frequent urination, and painful urination.