The thesis presents an innovative method to reduce the cost and synthesis temperature of highly porous mullite ceramics. The author researches the use of different doping additives to change the properties and structure of high temperature ceramics. The highly porous mullite ceramics are formed by slip casting method of concentrated suspension. Aluminium paste is used as pore forming agent, which after reaction with water in alkaline medium, forms hydrogen gas. The change in characteristics was achieved by partial replacement of expensive Al2O3 and SiO2 with cheaper kaolin, as well as use of metal oxide doping additives, such as MgO partially stabilized ZrO2, WO3 and MgO. High-resolution field emission low vacuum electron microscope "FEI Nova NanoSEM 650", mercury porosimeter "Pore Master 33 Quantachrome Instrument", acoustic system "Buzz-O-Sonic 5.0", differential thermal analysis and derivatograph "SETSYS Evolution TGA-DTA/TMA SETARAM (1750oC)" and others were used to define the properties of synthesised porous mullite ceramic. The results show that the presence of the doping metal oxides significantly alters the process of mullite phase formation in compositions after sintering at the various temperatures. Thermal conductivity depends on the porosity of the ceramic material, pore size distribution and doping additives. WO3 as a doping additive changes the processes of ceramics’ synthesis and the properties of ceramics, makes it possible to synthesise the highly porous mullite heat insulation ceramics with high thermal shock resistance.