For the first time, mesoporous nickel–titanium-trimesic acid (NTT) inorganic–organic hybrid composite was synthesized in water-in-[Bmim]PF6 ionic liquid microemulsions using the trimesic acid (BTC) as the linker. The synthesized NTT was characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) analysis, powder X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) methods, etc. Then, the isotherm and kinetic of adsorption were studied. The experimental data were well fitted with isotherm models of Langmuir and Freundlich (IMLF) at 298 K and 308 K and better fitted with the isotherm model of Langmuir (IML) at 318 K with the adsorption capacity of 662.212 μmol/g (maximum). The adsorption of rhodamine B (RhB) on NTT can be described by pseudo-second-order (PSO) kinetic model. This proposed method for synthesis of mesoporous NTT inorganic–organic hybrid composite is facile, environment-friendly and operated at room temperature, which could be applied to synthesis of other mesoporous inorganic–organic hybrid composites.