By employing a GaN-based series-biased micro-light emitting diode (μLED) array and orthogonal frequency division multiplexing modulation format, a high-speed free-space visible light communication system for long-distance applications has been demonstrated. The blue series-biased μLED array, which consists of 3 × 3, 20 μm-diameter μLED elements, presents promising performance with an optical power and -6dB electrical modulation bandwidth of over 10 mW and 980 MHz, respectively. Record data transmission rates have been successfully achieved at different free-space distances. Within 5 m transmission distances, over 10 Gbps data rates at the forward error correction (FEC) floor of 3.8 × 10 -3 are accomplished. Extending the transmission distances to 20 m, the data rates are maintained at the Gbps level at the FEC floor.