The invention provides a nano-material for compounding CdZnS quantum dots and carbon dots, a preparation method of the nano-material and an application. The nano-material comprises nano-particles, a plurality of CdZnS quantum dots are uniformly dispersed and loaded on the carbon dots to form the nano-particles, the diameter of each CdZnS quantum dot is 4-8 nanometers, sulfide precursors and dispersion liquid with the carbon dots are uniformly mixed, and the nano-material is prepared by a solvothermal method. A preparation process is simple and easy to operate and control, the obtained nano-material is stable in nature and low in cost and can serve as a photocatalyst, the CdZnS quantum dots in the nano-particles are uniformly loaded on the carbon dots, aggregation of the CdZnS quantum dots is reduced, stability of the hydrogen production process of substances can be improved, and hydrogen production efficiency is improved.