Relaxation processes over the static permittivity frequency region present in poly(propylene glycol) [PPG] of average molecular weights Mn=425 and 725 have been investigated in the temperature range (285–320 K) and frequency range (1 Hz–1 MHz) using broadband dielectric spectroscopy. The data have been compared in the form of complex dielectric permittivity (ε*), electric modulus (M*), conductance (σ*), and impedance (Z*) spectra of PPG. From the comparative analysis of the spectra of all the complex quantities, the temperature-dependent relaxation processes caused by the presence of electrode polarization and ionic conduction efects were explored. The temperature dependence of various dielectric parameters such as dc conductivity (σdc), relaxation time due to electrode polarization (τEP), conductivity relaxation time (τσ), and their activation energies have been critically examined. It was observed that the dependence of dc conductivity (σdc) on the viscosity (η) or structural relaxation time (τα) of both PPGs satisfes the Stokes–Einstein–Nernst/Stokes–Einstein–Debye quite well. This behavior is similar to those reported in lithium percolate (LiClO4) electrolyte solutions in PPG solvents. This demonstrates that the electrical conduction behavior of unknown ions impurities existing in pure PPG and extremely low known concentration added ions in pure PPG is the same.