An intelligence-defined optical tunnel network system includes multiple Optical Switch Interconnect Sub-systems (OSIS), in which a first OSIS is configured to transmit a first lateral transmission optical signal via a first line to a second OSIS, and transmit a second lateral transmission optical signal via a second line to the second OSIS. The second OSIS includes a failover sub-module and a micro-control unit. The failover sub-module is configured to output one of the first and the second lateral transmission optical signal based on a selective signal. The micro-control unit is configured to output the selective signal to the failover sub-module to control the failover sub-module output the second lateral transmission optical signal if a signal intensity of the first lateral transmission optical signal is lower than a threshold value.