The nanofibrous ammonium titanate (NH4)(2)Ti3O7-xNx was hydrothermally synthesized by a new method proposed here from titanium oxysulfate precursor in a NH4OH solution under hydrothermal conditions at 393 K without any extra templates. The calcination of the as-synthesized material at 673 K produced nitrogen-doped titania (TiO2-xNx) with anatase phase, which absorbed visible light and had an extremely high surface area (377 m(2) g(-1)). This material showed an excellent photocatalytic activity in decomposition of 2-propanol under visible light irradiation.