The invention discloses an inflaming retarding sponge, which comprises the following raw materials of, by weight, 100-120 parts of polyether polyols, 65-70 parts of toluene diisocyanate, 15-23 parts of biphenyl phosphate, 10-30 parts of polyoxosilane, 0.05-0.5 parts of triethylenediamine, 0.1-1.0 parts of stannous caprylate, and 4-5 parts of water. In the invention, the fire retardant biphenyl phosphate is added to the traditional sponge foam material to prepare the inflaming retarding sponge, which does not combust in case of fire, but is melted by heating, thus hidden danger of a fire accident can be reduced, and black smoke generated in carbonization is reduced. The inflaming retarding sponge not only possesses characteristics of traditional sponge such as good elasticity, high pullingforce, etc., but also possesses advantages of simple production technology, flame retardation, safety, environmental protection, etc.