The invention relates to a preparing method of a high-stability copper-based electric contact material, and belongs to the field of electronic element material preparing. Through ferric chloride and aluminum nitrate as raw materials, copper powder is doped, copper aluminum hydrotalcite is prepared, the hydrotalcite serves as an interface bonding agent, through Ti3SiC2 and copper powder composite burning, the phenomenon that due to the chemical potential difference of the material under the high-temperature environment, atoms between the interfaces are driven to diffuse is avoided, the hydrotalcite serves as the combination interface, a ceramic base body and copper powder particles are subject to wrapping, a large number of fresh surface layers and strong combination faces can be formed, the contact area of the contact material can be increased, the diffusion distance is shortened, diffusion compatibility is achieved, stability of the contact interface in the material can be effectively improved, meanwhile, through the interface modified effect, the mutual permeation effect of the ceramic base and the metal material can be improved, generation of holes in the material can be reduced, the material compactness is improved, and therefore the material conductive strength can be effectively improved.