The augmentation effect of electrohydrodynamically (EHD) induced flow disturbance on forced-convection heat transfer in a channel was experimentally investigated. This study was carried out with the unique point that the flow near the wall is disturbed actively and controllably by applying electric fields between the wall and array of wire electrodes installed near the wall along the main stream. The liquid mixture of refrigerant R113 (96wt%) and ethanol (4wt%), called Fronsorubu AE, was selected as a working fluid. Heat transfer was found to be promoted intensely in the trubulent flow as well as in the laminar flow, up to a factor of about twenty-three in the case of laminar flow. It is noteworthy that the rate of increase in heat transfer coefficient is larger than that in the pressure drop. From the measurement of velocities by a laser Doppler velocimeter, it was clarified that the electrohydrodynamically induced flow disturbance brings about large heat trasfer coefficients.