The insulating refractory products have a porosity of not less than 45%. Its main characteristics are high porosity, low bulk density, low thermal conductivity, low heat capacity and good thermal insulation performance. They are both heat-insulating and heat-resistant. They are generally used as insulation layers for various thermal equipment, and some can also be used as working layers. They are energy-saving materials for building various furnaces. Replacing general dense refractory products with insulating refractory products as building materials can reduce heat storage and heat loss by 40%-90%, especially for discontinuous thermal equipment.