An optical communication system comprises N server racks, first and second distribution frames, and first and second optical fiber cables. Each of the first and second optical fiber cables has N optical connector groups for racks and an optical connector group for distribution frame including M optical connectors. The closer the number of an optical connector of the M optical connectors is to the last number, the longer a wiring distance from the optical connector group for distribution frame to a corresponding optical connector group of the N optical connector groups for racks in the first optical fiber cable. The closer the number of an optical connector of the M optical connectors is to the last number, the shorter a wiring distance from the optical connector group for distribution frame to a corresponding optical connector group of the N optical connector groups for racks in the second optical fiber cable.