Electrospinning technology has great advantages in the preparation of nanofiber materials. To improve actual usage of nanofibers for innovative applications, these nanofibers can be assembled into nanofiber yarn. Nanofiber yarn devices can be divided into different types based on the different principles, which are as follows: the auxiliary electrode collecting device, self-bundling spinning device, water bath method collecting device, single needle electrospinning yarn device, double electrode disc twisting electrospinning yarn device, and other nanofiber yarn devices. As for the different preparation methods and devices of nanofiber yarn, the mechanical properties of nanofiber yarn are compared and analyzed.