The invention discloses an active hydrogel and a preparation method thereof. The method comprises the following steps: by taking rat groin adipose tissues without capillary and muscular tissues as raw materials, preparing an adipose tissue-derived stromal cell conditional medium; by taking chitosan and hyaluronic acid as raw materials, performing cross-linking reaction on chitosan and hyaluronic acid under the effect of a cross-linking agent glutaraldehyde, thereby preparing a chitosan-hyaluronic acid compound gel; and fully mixing the adipose tissue-derived stromal cell conditional medium and the chitosan-hyaluronic acid compound gel, adhering the active factors of the adipose tissue-derived stromal cell conditional medium to the chitosan-hyaluronic acid compound gel, adding I type collagen and uniformly mixing, thereby acquiring the active hydrogel. The active hydrogel provided by the invention can be used for repairing the skin and muscle injury in operative wound, the regeneration effect of the skin and muscle can be greatly promoted and the active hydrogel is convenient in a use process, high in safety, simple in preparation method and easy in industrialization.