The invention relates to the technical field of materials of solid solution alloy powder used for cermet, in particular to the solid solution alloy powder used for the cermet and a preparation method.The main chemical formula of the solid solution alloy powder used for the cermet provided by the invention is (Ti, M) (C, N), wherein M is any one or consists of more than one of main active metal elements: W, Mo, Mn, Ta, Nb, Cr, V, Zr and Re; and the solid solution alloy powder comprises the following components: 10-50 % of main active metal M, 8.5-12.5 % of Ct, 8.5-12.5 % of N, not greater than0.35 % of Cf and the balance alloy element Ti. The preparation method provided by the invention overcomes the defects that high sintering temperature is needed in a sintering process when single-phase compound powder is added as a raw material traditionally and the bonding bone phase of cermet alloy is incomplete at the stage of forming a liquid-phase sintering solid solution; each active elementof the alloy is added as the solid solution in the raw material, so that the final cermet performance can be effectively reinforced; and the production technology is simple and easy to control, and is suitable for industrial production.