Single‐crystalline Fe3O4 nanorice has been prepared by a simple one‐pot, surfactant‐assisted hydrothermal method using dodecyltrimethylammonium bromide (DTAB) as a surfactant. X‐ray powder diffraction, field emission scanning electron microscopy (FESEM), TEM, high‐resolution (HR)TEM, micro‐Raman spectroscopy and magnetic measurements have been employed to study the properties of the product. The importance of NaAc and ethylene glycol in the formation of the pure magnetite phase has been established. The as‐synthesized products have a regular rice‐like shape with an average diameter of 150 nm and length of 500 nm and are monodisperse. Shape evolution from cauliflower‐ to rice‐like morphology has been achieved by controlling the DTAB concentration. A possible formation mechanism for the Fe3O4 nanorice is explored. Furthermore, the product showed ferromagnetic properties at room temperature.