The thermal sensing properties of carbon nanocomposites were studied in this work. Two kinds of carbon nanocomposites composed of thermoplastic polyurethane (TPU) and multi-walled carbon nanotubes (MWCNTs) were characterized by infrared camera and temperature dependence of their resistance. It was found that the carbon nanocomposites formed by TPU doping into MWCNT showed excellent electrical and thermal conductivity and better thermal stability.