Periplaneta americana, as a traditional Chinese medicine, is widely used in wound repair. We isolated and purified a heteropolysaccharide PAP55-1-2 (8.13 kDa) from Periplaneta americana medicinal materials, which is mainly composed of N-acetylgalactosamine, galactose, glucose and mannose, etc. Among them, the content of N-acetylgalactosamine is relatively high, with a large number of N-acetyl groups. Through the study of structure-activity relationship, it was found that the N-acetyl groups play an important role in the process of wound healing. Therefore, PAP55-1-2 was reacted with N, N'‑carbonyldiimidazole (CDI) in DMSO at 50 °C for 3 h, and then ethylenediamine was added and reacted for 48 h. By using this mild method, the amino-modified Periplaneta americana polysaccharide (PAP-AM) was prepared while retaining the N-acetyl groups and their activity, and then reacted with aldehyde-modified chondroitin sulfate (Chs-CHO) to prepare a hydrogel. The cross-linking mechanism is attributed to the Schiff base reaction between amino and aldehyde groups. Subsequently, we prepared kaempferol (Kae)-chitosan (CS) microspheres with a diameter of 89.01 μm by a modified emulsification method, and then embedded them into high-dose PAP-AM hydrogel (PH-C) to produce a composite scaffold. The composite hydrogel Kae-CS@PH-C has good biodegradability, injectability, adhesion, self-healing and mechanical properties. In addition, it can accelerate the wound healing process in mice through antibacterial, hemostatic, antioxidant and immunomodulatory activities. These experiments indicate that the composite hydrogel has potential for biological applications.