Abstract: A visible light communication system, and a method of modulating data and a method of feeding back performance information in the system, are provided. In the system, a transmitting unit modulates a plurality of data on a plurality of LED channels basis that are formed by a plurality of LEDs, respectively, and transmits the modulated data into a corresponding light signal. A receiving unit receives a light signal that is transmitted from the transmitting unit to demodulate the received light signal to a signal on a plurality of LED channels basis.