Electrohydrodynamic heat transfer enhancement of natural convection inside the finned vertical channels is investigated via a computational fluid dynamics technique. The interactions between electric field, flow field, and temperature field are numerically determined. Flow and heat transfer enhancements are significantly influenced at low Rayleigh number. The effect of electrode arrangement and number of electrodes to the average velocity and Nusselt number are expressed. An optimum inclined angle of the channel is recommended. Relation between the number of fins and fin length to the augmented flow and heat transfer is also analyzed.