The spectra of the dielectric constant vs. the measuring temperature and of the dielectric constant vs. the measuring frequency for the nanostructured rutile bulk samples prepared under different pressures were investigated. It can be observed that when the measuring frequency ω2 times higher than that in the high frequency range. Furthermore, with the increment of the pressure, the dielectric constant rises and dielectric loss decreases and shifts towards the low frequency. For the samples formed under 1.0 GPa, two peaks appear in the spectrum of dielectric constant vs. the measuring temperature, and their peak positions are 50℃ and 300℃ , respectively. According to dielectric polarization theory, it can be supposed that high dielectric constant of nanostructured rutile arises mainly from the electronic relaxation polarization, which takes place inside the particle components of nanostructured rutile, and the rotation direction polarization, which is established in interfaces of nanostructured rutile, The 50℃ peak and the 300 ℃ peak are, respectively, attributed to the electronic relaxation polarization and the rotation direction polarization.