An optical multi-ring network for burst data communication is disclosed. The multi-ring network includes a plurality of optical single-ring networks having a plurality of optical add/drop routers connected with each other through fiber links, and a core optical router for supporting communication between the optical single-ring networks. The core optical router includes a wavelength division demultiplexing section for demultiplexing optical signals received from the each single-ring network and outputting the demultiplexed optical signals as channels whose wavelengths are different from each other; a branching section for branching off and outputting a portion of each channel; and a switching section for switching each channel to a path directed to the destination of each channel according to a first control signal. The core optical router also includes a contention resolution block for aligning channels in a chronological order, which are output at the switching section and directed to identical destinations, according to a second control signal; a wavelength division multiplexing section for collecting channels which pass through the contention resolution block according to destination and outputting the collected channels as multiplexed optical signals; and a controller for recognizing a destination of each branched channel input from the branching section and outputting a third control signal to the switching section and the contention resolution block so as to a low each channel to be directed to the destination of each channel. A frame transmitted on the multi-ring network includes a burst datum consisting of a plurality of packet data, and a header datum indicating a destination of the burst datum.