The invention belongs to the technical field of steelmaking converters, in particular to a masonry structure for an 18TAOD furnace lining, which comprises a furnace bottom and a furnace wall; the bottom of the furnace wall is provided with a blower gun; an area spread in a sector shape on the upper part of the blower gun on the furnace wall is an airhole area; the first layer, the second laeyr and the third layer of the airhole area are made of magnesite-chrome bricks; the fourth layer, the fifth layer, the sixth layer, the seventh layer, the eighth layer, the ninth layer and the tenth layer are made of high-purity magnesia-calcium bricks; and the eleventh layer, the twelveth layer, the thirteenth layer, the fourteenth layer, the fifteenth layer, the sixteenth layer, the seventeenth layer, the eighteenth layer and the nineteenth layer and other furnace wall are made of common magnesia-calcium bricks. In the masonry structure, the whole furnace lining is basically uniform through reasonable use of refractory bricks made of different materials in different areas so as to achieve the aims of improving the furnace life and reducing the cost.