In this paper, the variation of coefficient of friction, which is one of the main and important parameters in fretting fatigue, has been investigated experimentally. Measuring of coefficient of friction has been performed with the designed device by the researchers. The advantage of using the above device is that it can almost accurately measure the contact pressure and friction force and thus the coefficient of friction. Al alloy 2024-T3 has been used as it is the frequently used alloy in aerospace structures. The coefficient of friction is considered here as a parameter which is a function of normal and cyclic axial load. Another important point in performing the test is the variation of frictional stress at different normal and axial loads which is measured. Results show that as the normal load increases, the coefficient of friction reduces but the frictional stress increases. Changing the frictional stress is the main parameter in investigating wear between interfaces. The above results can be applied in numerical analyses such as life prediction and/or predicting joints fracture section such as double shear lap joints which experience fretting fatigue.