Iron oxide micro and nanoparticles were successfully synthesized from Red Mud (RM) using a simple twostep process. RM was characterized using various techniques such as X-Ray Diffractometer (XRD), Fourier Transform- Infra Red (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX) analysis and Carbon Hydrogen Nitrogen (CHN) microanalysis. Red mud derived iron oxide micro and nanoparticles (RIMNP) were characterized using techniques such as XRD, FTIR, SEM/EDX, Transmission Electron Microscopy (TEM) and Vibrating Sample Magnetometry (VSM). RIMNP were employed as a Fenton like catalyst for the decolorization of a commonly used textile dye Reactive Blue 235 (RB235) from aqueous solution. The dynamical data obtained at different concentrations of RIMNP fit well with pseudo-second-order kinetic model and 100% dye removal efficiency was obtained at 200 mg L-1 concentration of RIMNP.