The invention provides a method for rapidly preparing ZrNiSn thermoelectric material and belongs to the technical field of thermoelectric material preparation. The method comprises the following steps: pressing mixed powder consisting of Zr powder, Ni powder and Sn powder into a green body; carrying out combustion synthesis reaction on the green body under the supergravity condition; and obtainingZrNiSn thermoelectric material after cooling. According to the method, the thermoelectric material is prepared by utilizing the combustion synthesis reaction under the supergravity condition, the material density is increased while avoiding grain growth, the heat conductivity of the crystal lattice of ZrNiSn thermoelectric material is reduced favorably, and the thermoelectric performance of the material is optimized. The result of the embodiment indicates that the the the thermoelectric figure of merit of the prepared ZrNiSn thermoelectric material can reach 0.65 at 923K. In addition, the preparation method also has the characteristics of being short in synthesis period and low in energy consumption and is suitable for large-scale industrial production.