A full-duplex orthogonal frequency division multiplexing-radio over fiber (OFDM-ROF) system with 40 GHz optical millimeter-wave generation by utilizing single-arm Mach-Zehnder intensity modulator and optical carrier suppression modulation in base station is proposed and experimentally investigated. In the downstream,2.5-Gb/s OFDM analog data and 20-GHz radio frequency clock are mixed and used to modulate optical carrier by driving optical intensity modulator. The signal at base station after transmission over standard single mode fiber is demodulated,received and analyzed. In the upstream,the same optical carrier is reused at base station for uplink connection of 2.5-Gb/s on-off keying data. Experimental results show that the downlink and uplink data is successfully transmitted over a 50-km single-mode fiber (SMF-28) with less than 1 and 0.5 dB power penalty,respectively.