Essential oils (EO) from plant materials are conventionally extracted using hydrodistillation, steam distillation, solvent extraction, and cold pressing. The most widely used method for EO production is distillation. Novel methods, including microwave-assisted extraction, supercritical fluid extraction, ultrasound-assisted extraction, and ohmic heating-assisted extraction, have recently been used to extract EO. Ohmic heating-assisted hydrodistillation (OHAH) is a promising method for EO production as it offers advantages such as rapid heating, higher EO yield, higher EO quality, and lower energy and time consumption compared to conventional distillation methods. Passing electrical current through a conductive medium such as food causes an internal heat generation called as “ohmic heating.” An OHAH system is formed by combining the Clevenger apparatus with an ohmic heating system. Controlling the heating rate, voltage gradient, and current is essential for the successful operation of OHAH. By adjusting these parameters, researchers and practitioners can enhance the overall performance of the extraction process, leading to improved yields and reduced energy consumption. This chapter provides details on the design and instrumentation of an OHAH system.