The present invention discloses a halogen-free fire retardation long glass fiber reinforced PET composite material, which comprises, by weight, 40-72% of PET, 2-6% of a toughening agent, 10-20% of a halogen-free fire retardation agent, 0.5-2.0% of a thermal stabilizer, 0.5-2.0% of a special PET nucleating agent and 15-30% of long glass fibers, wherein the long glass fibers are special LFT alkali-free continuous long glass fibers for PET. The prepared material has characteristics of high fluidity, excellent heat resistance, high rigidity, high impact, high dimensional stability, excellent fire retardation and high CTI value, wherein the test results show that the tensile strength is more than or equal to 100 MPa, the flexural modulus is more than or equal to 6500 MPa, the notched impact strength is more than or equal to 15 kJ/m<2>, the heat distortion temperature (1.80 MPa) is more than or equal to 245 DEG C, the fire retardation grade achieves UL94 1.6mmV-0, and the CTI value is more than or equal to 500 V. In addition, the high temperature and low temperature double melt infiltration tank series connection technology is adopted to solve the high temperature decomposition disadvantage of the halogen-free fire retardation agent.