In order to understand the dynamic behavior of polymer matrix carbon nanotube (CNT) composites, modification and the destructive action of a CNT itself and CNT which exists in resin are examined with the dynamic action observation using the nano probe TEM (Transmission Electron Microscope). In has been considered that it is quite difficult to fracture CNT by bending deformation. However, it is revealed in this test that MWCNT is fractured by strong bending. It is also found that a crack arises by repeating buckling by compression. Moreover, it is observed in this test in the composite material, that with progress of a minute crack, MWCNTs fell out from matrix polymer in the nano-tensile test.