Titanium dioxide was synthesized by the hydrolysis of titanium tetraisopropoxide (TTIP) in the presence of acetic acid, 2-propanol, and organic amines ( octylamine, aniline, and isobutylamine). H2O was supplied by an esterification reaction between acetic acid and 2-propanol ( denoted as H(2)Oe), and/or by intentionally adding it ( denoted as H(2)Oa). It was found that the quantity of H(2)Oa plays a crucial role in the morphology and porous structure of the final TiO2 product. Without the addition of H(2)Oa, 1D and porous TiO2 was synthesized. With the addition of H(2)Oa, and when the H(2)Oa: TiO2 molar ratio was in the range of 1: 1 to 60: 1, macroporous TiO2 microspheres possessing a large surface area and high thermal stability were obtained. When the H(2)Oa: TiO2 molar ratio exceeded 60: 1, porous TiO2 with an irregular shape was formed. The variation in the morphology and porous structure is attributed to the manipulation of the growth kinetics by the addition of water.