In this paper, an electromagnetic finite element analysis is performed to study the feasibility of Electrical Capacitance Tomography (ECT) method to estimate soot load amount in a diesel particulate filter (DPF). It is critical to accurately measure the soot load in a DPF in order to optimize the active regeneration process that clears the filter clogged with soot. Tetrahedral mesh was created with electrostatic solid element for this analysis. Because of the geometry of the DPF and the narrowness of some sections between holes, a very fine mesh was generated. The lines representing the outer edge of the filter were sectioned and joined into segments representing four non-contacting electrodes. A sensitivity map was created illustrating the effect a clogged filter on the internal electric field of the filter. Multiple scenarios representing various clogging configurations were simulated. These configurations included a fully clogged filter, the top-right quadrant of holes clogged, and the lower half of holes clogged. The FEA analysis demonstrated that with change of relative permittivity in the DPF due to soot plugging can be estimated by measuring the electrical potential across electrodes.