The invention relates to a rod-like titanium protoxide powder and a preparation method thereof, wherein the titanium protoxide powder is Ti3O5 powder, Ti4O7 powder, Ti5O9 powder, Ti6O11 powder, Ti7O13 powder, Ti8O15 powder or Ti9O17 powder. The preparation method comprises: (1) material preparing, wherein raw materials comprise titanium dioxide powder, a carbon reducing agent and a chlorine salt, and according to the chemical formulas of each titanium protoxide powder and the chemical reactions among the used raw materials, the mold ratios of the raw materials for preparing various titanium protoxide powders are calculated; (2) material mixing and drying; (3) sintering, wherein the mixed powder obtained in the step (2) is loaded into a heating furnace, heating is performed at a heating speed of 5-15 DEG C/min under a flowing inert gas to achieve a temperature of 700-1300 DEG C, a reduction reaction is performed for 2-8 h at the temperature of 700-1300 DEG C, and cooling is performed along with the furnace to a room temperature after the reduction time is achieved; and (4) washing and drying, wherein the titanium protoxide-salt mixed powder obtained in the step (3) is washed with deionized water 3-10 times, and then drying is performed to obtain the rod-like titanium protoxide powder.