The electric contact is one of the most primary elements to affect the reliability of the electric systems. Gold finish can maintain high contact reliability but increase the manufacture cost. In this paper, the effects of one sided gold plated contacts with various thickness of gold finish on the contact reliability were investigated. The failure mechanism of the one sided gold plated contacts under fretting conditions was analyzed. The contact life and the optimum thickness of the one sided gold finish under fretting conditions was achieved and compared. The effect of the curvature of the probes on the contact life was also discussed.