The objectives of the present study are to synthesize MIL-100(Fe)@Fe3O4 composite and to clarify its ability as an adsorbent for methylene blue dye. The magnetite (Fe3O4) was synthesized using iron precursor from the zircon mining magnetic waste. The MIL-100(Fe) was composited with magnetite using a room-temperature in situ synthesis method. The MIL-100(Fe)@Fe3O4 composite obtained was then characterized using the Fourier transform infrared spectroscopy and X-ray diffraction. The synthesized MIL-100(Fe) and MIL-100(Fe)@Fe3O4 were then used to adsorb methylene blue dye from aqueous phase. The maximum methylene blue removal from both adsorbents was obtained at pH of 9. The adsorption kinetics showed that the adsorption followed a pseudo second-order kinetics model with the rate constant values for MIL-100(Fe) and MIL-100(Fe)@Fe3O4 were 1.012 x 10-2 and 3.963 x 10-2 g/mg.menit, respectively. The results also showed that the adsorption isotherm of MIL-100(Fe) and MIL-100(Fe)@Fe3O4 follows the Langmuir isotherm for adsorption capacities were 137.70 and 151.47 mg/g, respectively. The results indicate that the iron content in the zircon mining magnetic waste as precursor for synthesis MIL-100(Fe)@Fe3O4 composite can be employed as an excellent adsorbent for removal of methylene blue dye from aqueous phase.