This paper focus on studying the behavior of velocity profile under force vibration for a different frequency (34, 48, 65 and 80 Hz) for lower annulus of Can Combustor. An experimental rig was designed at Babylon University /Iraq by the author. The Can Combustor tested in this study is real part collected from Al-Khairat/Iraq gas turbine power station. The velocity profiles are examined at three positions in the annular for lower region. The velocity in X-direction calculating with a different frequency for lower annulus. The results were shown that the increase of frequency lead to increase the velocity profile and large recirculation zone will form in some points. Since the flow is turbulent, So the slope of the velocity profile at the wall is big but when forced vibration effect is applied it becomes much greater than without vibration effect about (25%).Reynolds number increasing with praise of velocity in X-direction. Also, the increase in vibration level produces non-uniform velocity profile which affects the spreading of cooling efficiency. Finally the shape of velocity profile change from flatter to non-uniform shape due to fluctuation vibration effect so, the cooling film air fails to protect the linear wall of Combustor from damage.