The present work has been carried out for in-depth study of the role of ions in dielectric heating. Aqueous solutions with ions having different charge, size, and nature were heated in a modified oven producing microwaves of 2.45 GHz at 900 W. For comparison, urea and sugar solutions were also subjected to investigation under similar conditions. The results can be helpful in better understanding the role of ions and their concentrations in microwave heating in domestic ovens.