As for practical application, ultrathin two-dimension (2D) materials have exhibited high performances in photocatalysis, electrocatalysis, and supercapacitors. Usually, when used 2D TiO2 (B) nanosheet as a photocatalyst, it absorbs only ultraviolet light, and several approaches have been taken to narrow the band gap of TiO2. Thus, we demonstrated a facile and environmental friendly method to enhancing hydrogen production by introducing defects of O vacancy and Ti3+ in surface and bulk TiO2 (B) nanosheets through the ambient-temperature plasma engraving treatment. After plasma treatment, the band gap of the 2D TiO2 (B) nanosheets decreased from approximately 3.13 eV-2.88 eV and the H-2 evolution performance of them is almost twice as high as pristine TiO2 (B) nanosheets under AM 1.5 illumination. The enhanced photocatalytic performances arise from the doping defect of O vacancy and Ti3+, narrowing the energy band gap and increasing more active sites of material surface with function of plasma engraving. The findings in this work may provide a new approach for improving the photocatalytic activities of other metal oxides.