Abstract: The treatment of carbon nanotubes (CNTs)，such as surface modification and local activation-modification，and the preparation methods of CNTs/PU composites，such as physical blending and in-situ polymerization，are introduced. The properties of CNTs and PU are presented，and the application of CNTs/PU composites，particularly in the aspects of improvement of mechanical propertiess，electronic materials，intelligent material，biomedicine and energy saving are reviewed. The suggestions about future study of CNTs/PU composites are also presented.