Titanium hydroxide precipitate was obtained by the reaction of 0.5M TiOCl2 and 5M NH4OH solutions, then anatase TiO2 powder with nanotubes was prepared by the digestion of the heat-treated powder in 5M NaOH solution. Nanotube was formed for anatase TiO2 powder digested at 10$0^{circ}C$ above, and the amount and length of nanotube increased with the digestion temperature. In the case of the powder digested at 15$0^{circ}C$ for 12h, the formed nanotube was 100~150nm in length, 10~20 nm in diameter, and 2nm in width of the walls on both sides of the nanotube. The powder digested at 15$0^{circ}C$ for 12h showed the highest specific surface area of 270$m^2$/g.