In this paper, we propose a fair semi-distributed resource allocation scheme over relay-enhanced orthogonal frequency-division multiple access (OFDMA) cellular networks. Since the existing works based on the centralized manner require the heavy feedback overhead between a base station (BS) and relay stations (RSs), we design a resource allocation scheme in the semi-distributed manner to reduce the feedback overhead. In the proposed scheme, a frame is divided into subframes and the BS and RSs allocate the subchannel in the dedicated subframe to its associated mobile stations (MSs). In addition, the proposed scheme guarantees fairness among MSs with the throughput-optimal scheduling. Through the simulation, we show that the proposed scheme is effective to guarantee fairness among MSs while it achieves the higher average throughput than the existing opportunistic schemes.