The invention provides a preparation method of zinc sulfide quantum dot/gelatin nano-composite with reversible sol-gel transition performance. The method is characterized by comprising steps as follows: 1) preparing a sodium sulfide solution; 2) preparing a zinc acetate/gelatin mixed solution; 3) preparing a zinc sulfide quantum dot/gelatin nano-composite; 4) observing the reversible sol-gel transition performance of the zinc sulfide quantum dot/gelatin nano-composite. The method has the advantages of being novel, simple, convenient, environmentally friendly, mild in preparation condition, simple and convenient to operate, easy to control, good in repeatability and low in cost and adopting simple instrument and equipment. The composite has the fluorescence property of zinc sulfide quantumdots, also has temperature stimuli-responsive reversible sol-gel transition performance and can be used for preparing doped zinc sulfide quantum dot/gelatin nano-composite such as a manganese-doped zinc sulfide quantum dot/gelatin nano-composite. The zinc sulfide quantum dot/gelatin nano-composite has good application prospects in the fields of fluorescence radiation materials, nano-composites, fluorescent biomaterials and the like.