The invention relates to an antibacterial modification method for collagen. The antibacterial modification method for the collagen comprises the following steps: (1) preparing collagen aqueous solution with the concentration of 2-70wt%, adjusting pH to be 7-13, and warming to the temperature of 30-100 DEG C; (2) adding modified triclosan into the collagen aqueous solution treated after the step (1), reacting for 0.1-24 hours while stirring and keeping the temperature to be 30-100 DEG C, then stopping reaction, and adjusting pH of solution to be 6-8, so that an antibacterial collagen solution is obtained. The prepared antibacterial collagen has the advantages that an antibacterial component is firmly bonded into collagen by virtue of a covalent bond, an antibacterial effect is more lasting, and the antibacterial property can be shown in the whole service cycle if the antibacterial collagen is prepared into antibacterial type protein gel.