With the popularity of wireless networks, it needs to support user¡¦s mobility cross different base stations, hence, the handover mechanism becomes an important issue. When the user frequently moves between two cells, it will occur the Ping-Pong effect that increases the delay time and reduces the efficiency of system. In this thesis, we proposed a new handover mechanism by considering the fractional frequency reuse (FFR) over relay networks to reuse frequency in multi-cells. The proposed method can reduce the unnecessary handover caused by the interference in the system of FFR. It uses the value of signal to interference and noise ratio (SINR) and the parameter of distance to make handover decision. The simulation results indicate the proposed handover mechanism can reduce more than 8% of the handover number in average in comparison to the competing method in the best case.