The invention discloses a high-temperature-resistant heat-insulating 
protective garment and a preparation process thereof, and relates to the field of protective garments, and the high-temperature-resistant heat-insulating 
protective garment is prepared by selecting a polysulfonamide fabric, performing 
flame-retardant finishing by using an after-finishing 
flame retardant, soaking the polysulfonamide fabric in an anti-static liquid, dipping, 
drying, and 
coating the surface of the fabric with a 
polytetrafluoroethylene coating, thereby obtaining the high-temperature-resistant heat-insulating 
protective garment. The anti-static breathable layer, the heat 
insulation layer and the 
flame-retardant layer are sequentially compounded, and the problems that an existing protective garment is poor in heat insulation performance, cannot well block 
heat energy outside the protective garment and is not ideal in flame-retardant effect are solved; the compounding of organic and 
inorganic materials can realize complementary advantages, and gives consideration to the 
mechanical property, weaving property, heat insulation and 
open fire resistance of polysulfonamide, so that the heat insulation property of the fabric is improved, the flame-retardant layer can prevent 
combustion products from escaping and inhibit 
thermal decomposition of materials under the layer, the flame-retardant, low-
smoke and low-
toxicity effects are achieved, a cracked 
carbon layer is formed on the surface of the polysulfonamide, and the flame-retardant, flame-retardant and flame-retardant effects are achieved. And the 
oxidation resistance of the cracked 
carbon layer is improved, so that the flame-retardant purpose is achieved.