Monodispersed titania spheres with particle diameters in the range 600-800 nm were successfully synthesized based on hydrolysis and condensation of titanium tetraisopropoxide (TTIP). The preparation was performed using dodecylamine (DDA) or ammonia as catalyst in methanol/acetonitrile cosolvent at room temperature. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen sorption measurement. Combination of methanol/acetonitrile cosolvent were suitable for preparation of the monodispersed spherical particles. The average particle size of titania spheres prepared using DDA was larger than that of titania spheres prepared using ammonia. Using ammonia, the particles had a smooth surface. On the other hand, using DDA, the particles had a nanoscale rough surface with high monodispersity in particle size. The monodispersity was maintained even after crystallization of titania particles by the annealing at high temperature. The particle size uniformity and photocatalytic reactivity of the titania prepared using DDA was higher than those of the titania prepared using ammonia.