Abstract: The crystallization, conductivity, tensile properties, and response behavior of multiwall carbon nanotubes-polyurethane/polypropylene (MWCNTs-TPU/PP) composites were prepared by solution -melting method and systematically investigated. The introduction of MWCNTs can improve the conductivity and crystallization properties of the MWCNTs-TPU/PP composites, in which the mass fraction of conductive percolation value is about 1.9wt% and the onset crystallization temperature is increased from 117.5℃ to 131.2℃. Through the combination of resistance meter and temperature control device, the construction and destruction process of conductive network under different thermal treatment temperatures were characterized online. With the increase of thermal treatment temperature from 110℃ to 175℃, the conductivity and crystallinity were improved. The introduction of TPU can significantly reduce the reaction time of MWCNTs-TPU/PP composites to temperature from about 10 min to about 3 min, and the temperature response behavior has been significantly improved. The analysis of tensile data shows that the increase of MWCNTs content can improve the tensile strength and elongation at break of the MWCNTs-TPU/PP composites. When the addition amount of MWCNTs is 2.5wt%, the tensile strength of the MWCNTs-TPU/PP composites increases from ~35 MPa to ~47 MPa. The strain-resistance data shows that the introduction of TPU can improve the returnability of the strain and the stability of the conductive network structure in the process of cyclic tension.