Mesoporous TiO hollow spherical nanostructures with high surface areas were successfully prepared using a microwave method. The prepared hollow spheres had a size range between 200 and 500 nm. The spheres consisted of numerous smaller TiO nanoparticles with an average diameter of 8 nm. The particles had an essentially mesoporous structure, with a pore size in the range of 2-50 nm. The results confirmed that the synthesised of anatase TiO nanoparticles with specific surface area approximately 172.3 m g. The effect of ultraviolet and visible light irradiation and catalyst dosage on the TiO photocatalytic activity was studied by measuring the degradation rate of methylene blue. The maximum dye degradation performances with low catalyst loading (30 mg) were 99% and 63.4% using the same duration of ultraviolet and visible light irradiation, respectively (120 min).