Abstarct: Fluid flow is at the heart of many natural and man-made systems inside channels. Heat and mass transfer is accomplished across the channel walls in biological systems, such as the brain, lungs, kidneys, intestines, blood vessels, etc., as well as many man-made systems, such as heat exchangers, nuclear reactors, desalination units, etc. In recent years, considerable progress has been made in the field of miniaturization. It is now effectively possible to miniaturize all kinds of systems—e.g. mechanical, fluidic, electromechanical, or thermal—down to submicrometric sizes. By minimizing systems, new physical phenomena such as electrokinetic phenomena appear. One of these phenomena is the electrossmotic flow. Electrossmotic phenomena, unlike classical fluid mechanics, which causes the fluid flow of the pressure gradient, drives the fluid through the electrical potential difference. The Heat transfer of electrossmotic fluid flow has recently been considered by researchers In this research, the distribution of heat transfer of electrossmotic flow has been investigated. Since the study of the distribution of the field of electrossmotic flow velocity is of great importance, an analytical solution is presented for the distribution of the Newtonian fluid electrosmotic flow velocity in a curved two-dimensional micro channel. In another part of this study, the distribution of electrosmottic flow heat transfer in a curved three-dimensional micro channel has been numerically studied. By investigating the heat transfer distribution, the influence of various parameters such as joul heating, surface charge zeta potential, micro-channel electric field and dimensional parameters on the heat transfer distribution have been discussed