Related to is the field of polymer materials, and particularly related to are a method for preparing cross-linked hyaluronic acid gel and a cross-linked hyaluronic acid gel prepared by the method. Under an alkaline condition, a disulfide cross-linking agent is dropwise added into an alkaline solution of hyaluronic acid for cross-linking reaction, and after the reaction is completed, dialysis and freeze drying are carried out to obtain the cross-linked hyaluronic acid gel. A new disulfide cross-linking agent N,N-bis(acroloyl)cystamine is introduced, and it effectively solves degradation regulating problems of cross-linked hyaluronic acid; the disulfide bond ratio is controllable, which can effectively improve a cross-linking modification degree ratio in the cross-linked hyaluronic acid, thereby solving the problem of difficult degradation of highly cross-linked hyaluronic acid gel in the past. The cross-linked material has potential applications in aspects of drug carriers and tissue engineering scaffolds.