Thermal drawing process has emerged as a promising manufacturing process to generate high-throughput, well aligned, and indefinitely long micro/nano structures. Here we experimentally show that polymer fibers containing micro/nano metal wires were produced via thermal drawing process. Indefinitely long polymer fibers containing continuous, wellaligned Sn microwires were produced. Further drawing results in Sn wires with a size in micro and nanoscale (less than 400nm) and a length of over 100 μm. This thermal drawing approach provides new route to the fabrication of polymer fibers containing micro/nano elements for widespread applications.