Fermosecond time-resolved diffuse reflectance measurement was carried out for anatase and rutile TiO2 powder systems in air. Anomalous rapid decay in the first few picoseconds after a rise in absorption was observed in both anatase and rutile TiO2 powders when TiO2 powder was excited by light pulses of near-band-gap energy, while it was not observed in the case of over-band-gap irradiation. These results suggest that the recombination dynamics does not depend on the crystal structure, if the wavelength dependence is normalized using energy relative to their absorption edges.