An efficient microwave-assisted synthesis of TiO₂:(B) nanorods, using titanium tetraisopropoxide (TTIP), benzyl alcohol as the solvent, together with boric acid and oleic acid as the additive reagents, has been developed. Chemical modification of TTIP by oleic acid was demonstrated as a rational strategy to tune the shape of TiO₂ nanocrystals toward nanorod formation. The differently-shaped TiO₂:(B) nanocrystals were characterized in detail by transmission electron microscopy (TEM), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and nitrogen absorption-desorption. Oleic acid coordinated on the nanocrystal surface was removed by the reduction of its carboxyl group, and the photocatalytic activity of bare TiO₂ nanocrystals, under visible light irradiation, was also evaluated. The synthesized TiO₂ anatase nanorods exhibited a good photoactivity and completely degraded Rhodamine B solution within three hours.