Abstract: A new TiO₂/Mg(OH)2 multifunctional composite material was prepared by ammonia bubbling process.Nitrogen and iron codoped TiO₂ powder were obtained by the hydrothermal method using titanium tetrabutoxide as precursor and ammonium nitrate and Iron(Ⅲ) nitrate nonahydrate as nitrogen and iron source.The composite material was characterized by XRD,FE-SEM,FT-IR and TG.The results indicate that at 75 ℃,the particle size distribute uniformly(D₅₀=0.69 μm) with ammonia feeding time for 1h.SEM analysis shows that the flake-like hexagonal product is of good dispersibility.XRD analysis indicates that it's I₍₀₀₁₎/I₍₁₀₁₎=0.71.TG-DTA analysis indicates that the water loss was 24.9% of the total weight between 322 ℃ and 396 ℃ with the highest endothermic temperature at 376.2 ℃.The quality of samples could satisfy the demand of flame retardants.The photodegradation rate of the Rhodamine b is 56.3%.