A high strength multi-walled carbon nanotube (MWCNT)/shape memory polyurethane composite (SMPC) was prepared by in situ polymerization. The effect of MWCNT content and its dispersion on the microstructure, mechanical, and shape memory property of the SMPC were studied by scanning electron microscopy, universal testing machine, and dynamic mechanical analysis. The results showed that MWCNTs can be well dispersed in the composites and the composites with homogeneous dispersion of MWCNTs exhibited superior mechanical properties for MWCNTs supplied cross-link netpoints in the composites. And the materials with 97 % of recovery ratios (R-r) and 94 % of fixing ratios (R-f) indicated that this SMPC is a prominent potential candidate for smart actuator.