We have proposed a scheme of radio over fiber (ROF) system with octuple optical millimeter-wave (mm-wave) generation transmit orthogonal frequency division multiplexing (OFDM) signal based on odd order sidebands suppression technique and filtering. The transmission performance of the optical mm-wave OFDM signal is theoretically investigated and implemented by numerical simulation. The results show that the time shift induced by chromatic dispersion only causes a slight phase rotation for constellation diagram, and a 40GHz ROF system with a 2.5Gbit/s signal remain has a good performance after the signal is transmitted over 50km standard single-mode fiber (SSMF). Then the effects of the Mach–Zehnder modulator (MZM) DC-bias and modulation depth (MD) on the system performance are discussed by simulation, and the optimal performance of the system is obtained.