We propose and demonstrate a radio-over-fiber system to generate an optical millimeter wave (MMW) and realize wavelength reuse for an uplink connection. A tunable optical comb generated by a single Fabry–Perot laser serves as the optical source. The central carrier is separated by an optical circulator cascaded with a fiber Bragg grating. For the downlink, the unmodulated central carrier is coupled with one subcarrier, which has been modulated with data. Then, different MMWs can be generated by choosing different subcarriers. While for the uplink, the same central carrier is reused for an uplink connection with data. In the scheme, a 60-GHz MMW is obtained and the bidirectional data are simultaneously transmitted over 60-km transmission with power penalty. This system shows a simple cost-efficient configuration and good performance over long-distance delivery.