Abstract: Epoxy resin was mixed using melamine polyphosphate (MAPP) as intumescent flame retardant and titanate nanotubes (TNTs) as synergists to prepare flame retardant epoxy composites. TNTs were prepared by hydrothermal process and the synergistic effects of TNTs on the intumescent flame retardant epoxy composites were investigated by Limited Oxygen Index (LOI), vertical burning test (UL 94), SEM and Raman spectroscopy. The introduction of TNTs into the flame retardant composite enhanced the LOI value obviously. The flame retardant formulation (w_TNTs=2%) had the highest flame retardancy synergistic efficiency with the LOI value of 28.4% and Ⅴ-1 in UL-94. The introduction of TNTs decreased the mass loss of flame retardant materials and improved the thermal stability and the char formation property. Meanwhile, the graphitization degree of char residue was observed by Raman spectroscopy. With the addition of TNTs, the flame retardant formulation had the lower I_D/I_G value (intensity ratio of absorption peaks at 1 360 cm^-1 and 1 600 cm^-1) which resulted from the formation of the compact and dense char. Adding TNTs into flame retardant epoxy composites resulted in the enhancement of the composites flame retardancy and formation the compacted and dense char.