Open wounds are one of the concerns of modern medicine. Early on, before the wound has closed, bacteria can easily enter, leading to bacterial infections. Excipients with antimicrobial effects can greatly facilitate the wound healing process. In this work, we screened and synthesized the antimicrobial peptide Thr-Trp-Pro-Gla-Leu (TWPAL), which has good bacteriostatic effect as well as drug resistance. And by loading it into a hyaluronic acid/gelatin hydrogel, we developed an antimicrobial hydrogel (TWPAL-gel), and by analyzing the results of animal experiments, it was found that this treatment has obvious efficacy in the treatment of animal wound infections, which provides a strong experimental basis for the clinical treatment and an important reference value for the further research on the treatment of diseases. Therefore, a new antimicrobial peptide TWPAL and a hydrogel based on this peptide were developed in this study to provide a comfortable and sterile recovery environment for wound healing, which can be an ideal choice for the treatment of open wounds.