Trinity-intumescent flame retardant plays an important role in the synthesis of Halogen-free Flame retardant. Trifunctional(source of acid ,char-forming agent and blowing agent) is widely attracted more attention due to its high thermal stability、weatherability and better flame retardant、low smoke、low toxicity、low addition and good compatibility with polymer materials. Trinity-intumescent flame retardant including of three types of ring, cage and non-ring non-cage.Research of the recently of trinity-Intumescent Flame System was reviewed.