The birth of fiber optic technology makes the information transmission speed greatly improved, now we have entered a brand new stage of fiber optic technology application. In this stage, polymer optical fiber as a new type of optical fiber has attracted much attention. Due to the nature of its material, it is softer, lighter and cheaper than silicon fiber. At the same time, polymer fiber is more flexible than silicon fiber in terms of forming and handling, and can be customized for different needs and applications. With continuous improvements in manufacturing and properties, polymer optical fibers show strong potential and multiple applications in both transmission and sensing, such as fiber optic communications, physics research, health monitoring, biomedical and environmental monitoring. The applications of polymer optical fibers in these fields are presented in turn, the prospects of polymer optical fibers in fiber optic communication and sensing applications are summarized, and finally, future research directions are indicated.