This paper is concerned with the application of vibration simultaneously with artificial surface roughness techniques as a combined turbulence promoter for convective heat transfer enhancement. The study was conducted on a flat plate in perpendicular to flow and zero external pressure gradient for the free stream. For artif+cial roughness, grooves were made in the heat transfer surface and perpendicular to flow direction. Two different groove cross-sectional geometries were considered: V-shaped grooves and square-shaped grooves. The case of a non-grooved surface (natural roughness case which is also referred to as "smooth surface" case) was also considered. For vibration, two parameters were investigated; both for the smooth plate and the artificially-roughened one, namely: the frequency ( ranging from 0 to I00 H2) and the amplitude (ranging from 2mm to 20 mm). For a vibrated non-grooved (smooth) plate, experiment shows that vibration is a powerfül enhancement tool, the heat rate increasing more than 2.5 fold. Frequency and amplitude of the imposed vibration both have positive effect on heat transfer enhancement. The amplitude effect on heat transfer enhancement appears positive up to a certain limit. Here, increasing tne amplitude beyond a certain value produces an unexpected decrease in the enhanced heat transfer. This phenomenon may be attributed to the formationof an overlap boundary layer associated with large amplitudes. Moreover, the effect of frequency appears stronger than that of the amplitude. The results show also that the non-grooved plate differs from the grooved one (artificially roughened plate)