Electromagnetic wave scattering from a perfectly conducting indented body of revolution is analyzed both in the frequency and time domains. The three-dimensional (3-D) scattering process and the effect of polarization on scattering characteristics are revealed. A well-defined scattering matrix representation is adopted for investigating the polarimetric property of the 3-D scattering. First, the scattering cross sections are calculated in the frequency domain by using the Yasuura method (Mode-Matching Method) which is a powerful and reliable numerical method for solving electromagnetic boundary value problems. Next, co-polarization and cross-polarization components of the pulse response waveforms are calculated from the scattering matrix by using the Fourier synthesis technique. It is found out from the numerical results that the pulse responses from the indented objects can be interpreted as three distinctive waves: conventional specularly-reflected wave, creeping wave and complex specularly-reflected wave which is reflected from a complex specular reflection point. These scattering processes are consistently explained by employing the extended ray theory. And the radar polarimetries of these three distinctive waves are clearly observed both in co-polarization and cross-polarization components of scattering cross sections and pulse responses.