The invention discloses a fireclay insulating refractory brick NG130-1.0 and a preparation method thereof and relates to the technical field of manufacture of refractory materials. The fireclay insulating refractory brick is prepared from raw materials in parts by weight as follows: 20-30 parts of closed cell perlite, 10-20 parts of high-aluminum superfine powder, 10-15 parts of kaolin, 10-15 parts of bauxite, 10-15 parts of aluminum oxide powder, 10-15 parts of mixed powder and 12-14 parts of water. The raw materials have high refractoriness, and the fireclay insulating refractory brick NG130-1.0 is prepared from the raw materials through preparation, mixing, blank making, firing and the like in a certain ratio and is low in production cost, high in compression strength at the normal temperature and small in heat conductivity coefficient; the permanent linear change value of volume density, heating temperature and holding time is within the range value specified in GB/T3994-2013.