The heat transfer duty of heat exchangers can be improved by heat transfer enhancement techniques. In general, these techniques can be divided into two groups: active and passive techniques. The active techniques require external forces, e.g. electric field, acoustic or surface vibration etc. The passive techniques require fluid additives or special surface geometries. Electrohydrodynamic (EHD) techniques have been introduced as one of the types of active heat transfer enhancement techniques. This paper presents a review of research works on electrohydrodynamic heat transfer enhancement. This paper can be used as the first guideline for the researcher in using EHD techniques for heat transfer enhancement.