With the development of 5G, internet of things and big data, optical communication networks, as the backbone of data transmission, are imperative to expand their capacity, improve transmission stability and network intelligence. Space-division multiplexing technology, which is mainly based on multi-core fiber, few-mode fiber and few-mode-multi-core fiber, is considered to be the key to improve the capacity of optical communication network system and build next-generation optical communication networks. Based on the reported experimental results, the application of space-division multiplexed fiber was mainly studied in optical transmission, high-performance laser and fiber sensing. It is fully demonstrated that the space-division multiplexed fibers are important to the modern optical fiber communication system. It will be a hot spot and should be drawn much attention for the evolving optical communication.