The invention belongs to the field of cermet materials, and discloses a high-temperature-resistant cermet material and a preparation method thereof. The high-temperature-resistant cermet material comprises 11-22 parts of nickel sesquioxide, 5-11 parts of magnesium oxide, 7-11 parts of zirconium diboride, 2-4 parts of thorium dioxide, 4-7 parts of bismuth oxide, 5-9 parts of zinc, 7-13 parts of copper, 2-4 parts of germanium and 12-17 parts of iron. The preparation method comprises the following steps: (1) quickly mixing metals and a ceramic material at high speed; (2) carrying out ball milling on the uniform mixture with a ball mill; (3) carrying out high-temperature press fitting on the cermet material subjected to ball milling in a hot-pressing furnace, heating the furnace to 720-780 DEG C, keeping the temperature, continuing heating the hot-pressing furnace to 1520-1610 DEG C, sintering, and cooling to obtain the high-temperature-resistant cermet material.