The invention relates to the technical field of refractory materials. A magnesia zircon brick is prepared from the following components in parts by weight: 40 to 50 parts of alundum particles, 35 to 40 parts of fused magnesia particles, 2 to 10 parts of a-alumina micro powder, 5 to 8 parts of zirconium dioxide, 1 to 2 parts of fine silica powder, 15 to 25 parts of Fe2O3 powder, 2 to 5 parts of binding agents, 0 to 1 part of water reducing agent, 0.5 to 1 part of yttrium oxide, and 3 to 4 parts of calcium lignosulfonate. The invention also provides a preparation method of the magnesia zircon brick. The preparation method of the magnesia zircon brick comprises the following steps of: mixing raw materials, mixing and stirring in a blender mixer to obtain a mixture, then putting the mixture into a mold, performing pressing moulding, preheating a pressed green body, and then sintering the green body to obtain a finished product. The magnesia zircon brick and the preparation method thereof have the advantages of no pollution, high temperature resistance, corrosion resistance and thermal shock resistance.