This paper designs and implements a bi-directional voice intercom sys tem which is based on wireless visible light communication (VLC).Using a common 1W light-emitting diode (LED) flashlight as the transmitted light source for uplink and downlink,we finally r ealize the function of voice transmitting and lighting at the same time.The system adopts on-off-keying and not-return -to-zero (OOK-NRZ) modulation mode to modulate the signal,which is easy to realize and does not cost much.We desi gn the LED driver circuit and receiving circuit based on the measured LED photoelectric properties measured.T he single-chip microcomputer controls the audio codec chip to realize voice signal acquisition,processing an d transmission,and the voice data is transmitted through universal asynchronous receiver/transmitter (UART) interf ace.We realize a full-duplex and real time voice intercom system based on VLC with a maximum data rate of 2.5Mbi t/s and the transmission distance is as far as 40m.This system has a lot of advantages,such as low implemen tation complexity,low cost and low power consumption,and it can be applied in other data transmission situation s,not only the voice intercom system. Therefore,we can arrive at the conclusion that it has good practicability and e xtensive applicability.