In order to meet the needs of ultra-large capacity data transmission between ultra-big data centers, the researchers develop a coating diameter of 200 μm optical cable with 6912 cores. The structure and performance of 200 μm optical fiber and the key technologies of spider web fiber ribbon structure, optical fiber identification and left and right(SZ) stranding are introduced. After mechanical and environmental performance tests, the result show that the performance of optical cable with 6912 cores meets the requirements of optical cable standard and practical applicable.