The invention discloses a skin wound repairing hydrogel and a preparation method thereof. The skin wound repairing hydrogel contains aloe gum, chitosan, beta-glycerophosphate sodium and water, and has a pH value of 7.0 to 7.5. The preparation steps mainly include: at 2-10°C, mix 1-4% (w / v) chitosan solution and aloe gum at a volume ratio of 1:1-2, and then add β-sodium glycerophosphate solution dropwise , adjust the pH value of the solution to 7.0-7.5, and form a gel at 4-50°C. The skin wound repairing hydrogel of the present invention can promote the generation of skin capillaries, is beneficial to tissue growth, protects wound nerve endings, and relieves pain. It can be used for treating purulent skin diseases, superficial fungal skin diseases, skin trauma, and ultraviolet dermatitis. Anti-inflammatory, sterilizing, analgesic, absorbing heat, reducing swelling, softening skin, relieving pain, and improving scars.