A novel two-step method for the synthesis of monoclinic titanium oxide (i.e. TiO2(B)) nanosheets is pre-sented in this report. The method is featured by two steps: 1) synthesis of hydrogen titanate nanosheets, followed by 2) calcination of the titanate nanosheets at elevated tempera-tures. The hydrogen titanate nanosheets were prepared first by autoclaving anatase TiO2 powders, obtained by air cal-cining an ethanol-gel of Ti(OH)4 at 500℃, in aqueous NaOH (10 mol/L) at 150―200℃, and then by washing with hydro-chloric acid under supersonic irradiation. While sizes of the nanosheets were found to increase with increasing the tem-perature of the hydrothermal treatment, the calcination at 400―500℃ of the hydrogen titanate nanosheets that were synthesized at higher autoclaving temperatures (180―200℃) produced monoclinic TiO2 nanosheets with a uniform mor-phology. By contrast, the same calcination of the titanate nanosheets synthesized at the autoclaving temperature 180℃ led to anatase TiO2 nanoparticles. A novel two-step method for the synthesis of monoclinic titanium oxide (ie TiO2 (B)) nanosheets is pre-sented in this report. The method is featured by two steps: 1) synthesis of hydrogen titanate nanosheets, followed by 2) calcination of the titanate nanosheets were prepared first by autoclaving anatase TiO2 powders, obtained by air cal-cining an ethanol-gel of Ti (OH) 4 at 500 ° C in aqueous NaOH (10 mol / L) at 150-200 ° C, and then by washing with hydro-chloric acid under supersonic irradiation. While sizes of the nanosheets were found to increase with increasing the tem-perature of the hydrothermal treatment, the calcination at 400-500 ° C of the hydrogenated titanate nanosheets that were synthesized at higher autoclaving temperatures (180-200 ° C) produced monoclinic TiO2 nanosheets with a uniform mor-phology. By contrast, the same calcination of the titanate nanosheets synthesized at the autoclaving temperature 180 ° C led t o anatase TiO2 nanoparticles.