Wavelength division multiplexing transmission of chaotic optical communication and current optical communication is numerically confirmed and analysed. For a 100 GHz channel span，a 1-Gbit/s digital message extraction is achieved in chaotic optical communication system and a 2.5-Gbit/s digital signal is received in current optical communication system. The results show that when the peak power of digital signal in current optical communication is less than 17 dBm，chaotic optical communication can realise parallel transmission of 80 km. In addition，when the peak power of digital signal in current optical communication is 7 dBm，the quality of the received signal in current optical communication is hardly interfered by signals of chaotic optical communication. As the transmission distance increases from 80 km to 160 km，the opening of the corresponding eye diagram decreases from 82% to 70%.