A silk fibroin/chitosan composite smart hydrogel and a preparation method therefor. Silk is degummed, dissolved, dialyzed, centrifuged, and diluted to obtain a silk fibroin solution, the silk fibroin solution is then mixed with a dilute acid solution of chitosan, and the silk fibroin and the chitosan are crosslinked under the action of 1-ethyl-3-(3-dimethylaminopropyl)carbonyldiimide (EDC) and N-hydroxysuccinimide (NHS) crosslinking agents, to give a smart hydrogel. The hydrogel has excellent mechanical properties, good biocompatibility, biodegradability, and responsiveness to temperature, pH, and ionic strength among others. The hydrogel has broad application prospects in biomedical applications such as controlled drug release, tissue engineering scaffolds, and wound dressings. The smart hydrogel has a simple preparation method and a short process flow and can be batch manufactured easily.