The phase-based electrical properties tomography (EPT) derives the distribution of tissue’s conductivity using radi of requency phase information of magnetic resonance, which can be obtained by standard MR sequences. However, this method depends on the assumption that the conductivity value is much larger than the product of Larmor frequency and permittivity. In this study, we investigate the validity of this assumption under different electrical properties (EPs) distribution, which is conductivity and permittivity. This study simulates the birdcage coil loaded with a homogeneous phantom and obtains the simulation phase data with varied EPs. We calculate the reconstructed errors of conductivity images using the phase-based method and then analyze the relationship between these errors with EPs distribution. This work indicates that the suitable range of EPs is $ 2\omega\varepsilon \lt \sigma \lt 5\omega\varepsilon$ for the phase-based conductivity imaging at 3TMR, and it is useful for future clinical applications.