Abstract: TiO₂/MIL-100(Fe)/PA composites were prepared by means of in-situ growth method loading TiO₂ and MIL-100(Fe) on nylon (PA) at room temperature. FTIR, SEM, EDS, XRD and TG characterization methods were used to prove that TiO₂/MIL-100(Fe) was successfully loaded on PA. The effects of light, H₂O₂, dye structure, sodium chloride and pH value on the decolorization of TiO₂/MIL-100(Fe)/PA composite were discussed. The results show that the composite material has adsorption and decolorization effect for Reactive Black KN-B dye under dark condition. The decolorization rate of the composites for different reactive dyes is different under simulated solar light after adding H₂O₂. The decolorization rate for Reactive Black KN-B is the highest, followed by Reactive Brilliant Red M-3BE and Reactive Brilliant Blue KN-R. The decolorization rate can be reduced by adding NaCl in the dye solution, but the effect is not significant. The decolorization rate is decreased with the increase of pH value of dye solution.