We propose and demonstrate a photonic microwave up-conversion approach based on a self-starting optoelectronic oscillator (OEO). The OEO incorporating a dual-parallel Mach-Zehnder modulator (DPMZM) simultaneously works as a high-quality local oscillator and a broadband mixer to directly up-convert intermediate-frequency vector signals. The phase noise performance of the oscillation signal is proven to be independent of the vector signals. Through properly setting one dc bias of the DPMZM in the OEO, the dispersion-induced power fading for the up-converted signal in a radio over fiber transmission system can be compensated. In this experiment, 200 Mb/s 64 QAM signal at 2.4 GHz is successfully up-converted to 12.4 GHz by the OEO operating at 10 GHz and transmitted over 30 km single mode fiber without dispersion penalty.