Some fire-resistant epoxy resins known in literature and practice were reviewed. New unsaturated polyester resins with decreasing flammability was reviewed. The main monomers were dibromobutendiol and diallylic ether of dibromoneopentylglycol. The new idea of epoxy resin fire-retardance by creating new epoxy resin-unsaturated polyester copolymers was put forward and then obtained. The reagents were as follows: low-molecular epoxy resin, polyamine curing agent, special diazo-epoxy resin, brominated unsaturated polyester resins, styrene or diallylic ether of dibromoneopentylglycol as diluent to obtain optimum viscosity. The proposed mechanism to form three-dimensional copolymer network was presented.