We report the successfully preparation of straight and well faceted hexagonal-MoO₃ rods by a simple method consisting of a thermal treatment at low temperature applied to molybdenum diluited in a mixture of HCl and HNO₃. We have obtained sub-micrometer hexagonal rods several microns long with defect free walls. Electron scanning microscopy (SEM) and microRaman spectroscopy were used to characterize the obtained rods. Our results demonstrate the feasibility of synthesizing h-MoO₃ in a very simple way.