The invention relates to a ceramic/metal high-temperature packaging material of a gradient structure. A ceramic material comprises one or a plurality of nitrides (A1N, Si3N4, BN and the like), carbides (SiC, ZrC, TiC and the like) and oxides (Al2O3, SiO2, ZrO2 and the like). A metal material comprises one of high-melting-point metals, such as W, Mo, Ta, Cr and Nb. The preparing method of the material comprises the following steps: fully mixing required metal and ceramic powder according to designed gradient components, gradient layer number and the content of each component in each layer so asto obtain required raw materials for each gradient layer; stacking all layers and carrying out pressing forming; enabling the mass percent of ceramic powder to symmetrically and continuously vary ina gradient manner between 100 % and 0 % from the inner side to the outer side in the axial direction; utilizing a powder metallurgy and hot pressing co-firing technology, and finally obtaining the ceramic/metal high-temperature packaging material of the gradient structure. The helium leakage rate is smaller than 1x10<-11> Pa.m<3>/s, the bending strength is larger than 200Mpa, and the electric resistivity is larger than 6x10<9> omega.cm.