Uncontrolled hemorrhage is a major problem both in surgical intervention and after trauma. Herein, we design an in situ constructable peptide network, mimicking and participating in the native coagulation process for enhanced hemostasis and wound healing. The network consists of two peptides including C 6 KL, mimicking platelets and C 6 KG, mimicking fibrin. The C 6 KL nanoparticles could bind to the collagen at the wound site and transform into C 6 KL nanofibers. The C 6 KG nanoparticles could bind to GPIIb/IIIa receptors on the surface of activated platelets and transform into C 6 KG nanofibers. The in situ formed peptide network could interwind platelets, fibrin and red blood cells, causing embolism at the wound site. In a lethal femoral artery, vein, and nerve cut model of rats, the amount of bleeding was reduced to 32.8% by C 6 KL and C 6 KG with chitosan/alginate. The biomimetic peptides show great clinical potential as trauma hemostatic agents.