The invention relates to an active wound repair material, specifically to a functional dressing and a preparation method and application thereof, belonging to the field of medical materials. To overcome a technical problem, the invention provides the functional dressing, which belongs to biologically active wound repair materials. The functional dressing is prepared from the following raw materials by weight: 2 to 6 parts of biologically active glass, 12 to 20 parts of alginate, 4 to 12 parts of chitosan and 100 to 200 parts of water. Multiple dosage forms can be prepared from the above-mentioned raw materials, mainly comprising a gel, a dressing, etc. The functional dressing provided by the invention has the advantages of bacteriostatic action on a wound, promotion of wound healing and growth, adsorption of a small amount of tissue exudates, good biosecurity, waterproof performance, a bacterium blocking effect, etc. The functional dressing has a wide application scope, is applicable to mechanical trauma and operative incision (wound) and exerts a good therapeutic effect on hard-healing wounds like burns and scalds, diabetic foot, ulcer and pressure sores and a good curative effect on an infectious wound and a delayed union wound.