A method and system for implementing visible light communication, a sending apparatus and a receiving apparatus are disclosed. The method includes: after performing constellation modulation on data to be sent, a sending end mapping a modulated signal to a corresponding luminescent light source and transmitting the data to be sent through an optical signal; a receiving end converting a received optical signal into an electrical signal, and determining a constellation modulation signal according to a luminescent light source corresponding to the received signal, and demodulating the constellation modulation signal to obtain received data.